/ A TEXAS AGRICULTURAL EXPERIMENT STATION AGRICULTURAL AND MECHANICAL COLLEGE OF TEXAS W. B. BIZZELL, President BULLETIN NO. 308 APRIL, 1923 DIVISION 01= Enromomcar AQRICULTURAL 8L MECHANTCAL snEzrzsE OF TEXAS LIBRARY THE SWEET POTATO WEEVIL B. YOUNGBLOOD, DIRECTOR COLLEGE STATION, BRAZOS COUNTY, TEXAS . A240-423-15,000-L180 STATION STAFF? o ADMINISTRATION B. YOUNGBLOOD, M. S., Ph. D., Director CHARLES A. FELKER, Chief Clerk A. S. WARE. Secretary _ A. D. JACKSON, Executive Assistant CRARLEs Gonzvcxr, Technical Assistant M. P. l-loLLEMAN. JR.. Assistant Chief Clerk R. N. BURROWS, M. A., Research Librarian VETERINARY SCIENCE ‘M FRANcIs, D. V. M., Chief _ H SCHMIDT, D. V. S., Veterinarian V. J. BRAUNER, D. V. M., Veterinarian CHEMISTRY G S. FRAPs, Ph. D., Chief: State Chemist S. E. AsEuRY, M. S., Assistant Chemist 1S. LOMANITZ, B. S., Assistant Chemist WALoo WALKER, Assistant Chemist W. C. MITCHELL, B. S., Assistant Chemist A. G. PETERSON, B. S., Assistant Chemist HORTICULTURE H. NEss, M. S., Chief W. S. HOTCHKISS, Horticulturist ANIMAL INDUSTRY J. M. Jones, A. M., Chief R. M. Sherwood, B. S., Poultry Hiisbandman G. R. WARREN, B. S., Swine Husbandman J. L. LUSH, Ph. D., Animal Husbandman ‘ (genetics) _ _ _ L. M. MURPHY, Wool and Mohair Specialist J. D. SUNKEL, Dairyman "‘W. T. CARTER, JR., B. S., Chief H. W. HAwKER, Soil Surveyor H. V. GEIB, B. S., Soil Surveyor ENTOMOLOGY _ M. C TANQUARY, Ph. D., Chief : State Entomologist H. J. REINRARD, B. S., Entomologist . B. PARKs, B. S., Apiculturist . S. RUDE, B. S., Entomologist . H. ALEX. B. S., Queen Breeder . O. VICTOR, JR., Apiary Inspector g>nm AGRONOMY A. B. CONNER, B. S.. Chief A. H. LEmmR, B. S., Agronomist E. B. REvNoLns, M. S., Agronomist G. N. STRQMAN, M. S., Ayronomist; Farm Superintendent "PEARL DRUMMOND, Seed Analyst PLANT PATHOLOGY AND PHYSIOLOGY‘ J. J. TAUBENHAUS, Ph. D., Chief COTTON BREEDING %IG)FFPFIIR_?EMAN, DPChigj C .. . UMBERT, . ,, ' ' E. O. REA, B. S., Plant Breedermg h“! FARM AND RANCH ECONOMICS L. P. GABBARD, M. S., Farm and Ranch Economist R. N. WADE, Laboratory Assistant CONTROL ISVFRSVICE ' _ OUNGBLOOn. . Ph. D., Director F- D- FULLER, M S . Chief Inspector S. D. PEARcE, Inspector J. H. ROGERS, Inspector W. H. W000, Inspector J. J. KELLY, Inspector SUBSTATIONS No. l. Beeville, Bee County I. E. COWART, M. S., Superintendent No. 2. Troup, Smith County W. S. HOTCHKISS, Superintendent No. 8. Angleton, Brazoria County V. E. HAFNER, B. S., Superintendent ' No. 4. Beaumont, Jefierson County A. H. PRINCE, B. S., Superintendent No. 5. Temple, Bell County D. T. KILLOUGH, B. S., Superintendent No. 6. Denton, Denton County P. B. DUNKLE, B. S., Superintendent No. 7. Spur, Dickens County R. E DICKSON, B. S., Superintendent 1A: of April 1, 1923. W V leave. No. 8. Lubbock. Lubbock County R. E. KARPER, B. S., Superintendent No. 9. Balmorhea, Reeves County J. J. BAYLES, B. S., Superintendent No. l0. College Station, Brazos County (Feeding and Breeding Substation) L. J. McCALL. Superintendent No. ll. Nacogdoches, Nacogdoches County G. T. McNEsS, Superintendent "*No. 12. Chillicothe, Hardeman County A. B. CRoN, B. S., Superintendent No. 14. Sonora, Sutton-Edwards Countiol E. M. PETERS, B. S.. Superintendent D. H. BENNETT, V. M. D., Veterinarian ‘Wnjcoioplei-etilon‘with School of Veterinary Medicine, A. and M. College of Texao, **ln cooperation with United States Department of Agriculture. (1) In cooperation with School of AgricultuieA. and M. College of Texas. CONTENTS p 4 PAGE Introduction . . . . . . . . . ._. . . . . . . . . . . . . . . . ‘. . . . . . . . . . . . . . . . . . v History . . . . . . . .- . . . . . . . . . . . . . . . . . . . . . . . . . . . . .‘ . . . . . . . . . . . . . . '7 Distribution . . . . . . . . . . . . . . . . . . . . . . . .; . . . . . . . . . .. 9 Systematic Position . .1 . . . . . . . . . . . . . . . . . . . .- . . . . . '. . . . . . .i . . . . . . . 9 Allied Species . . . . . . . . . . . . . . . . . . . ..v .~ . . . . . ..' . . . . . . . . . .. 1]. Common Names . . . . . . . . . . . . . . . . . . . . . . . . . . .. 11 Economic Importance». . . . . . . . . . . 11 FoodPlants . . . . . . . . . . . . . . . . . . . . . . . . . . ..12 Methods of Study . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .‘ . .4 . . . . . . . 12 Life History .» . . . . . . . . . . . . . . . . . . . ; .' . . . . . . . . . . . . . . . . .' . . . . . . . . 12 Egg . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .._....13 Embryology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Hatching . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .‘ . . . . . . . . . . . 13 Duration of Egg Stage . . . . . . . . . . . . . . . . . . . . . . . . . . . .; . . . . . . 15 Larva . . . . . . . . . ..'. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 23 Description . . . . . . . . . . . . . . . . . . . . . . . .i . . . . . . ; . . . . . . . . . 23 Duration of Larval Stage. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 -Prepupal Stage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 32 Pupation . . . . . . . . . . . . . .» . . . . . . . . . . . . . . . . . . . .4 . . . . . . . . . . 32 Pupa . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Description . . . . . . . . . . . . . . . . . . . . . . . . . . .4 . . . . . . . . . . . . 32 Duration of Pupal Stage....v . . . . . . . . . . . . . . .. 34 Transformation to Adult . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42 - Adult . . . . . . . . . s.‘ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 42 Before Emergence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42 Emergence . . . . . . . . . -. . . . . . . . .4 . . . . . . . . . . . . . . . . . . . . . . . 43 Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .~. . 43 Summary of Development . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43 Feeding Habits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 45 Location of Food . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45 Length of Life of Adults Without Food . . . . . . . . . . . . . . . . . . . . 47 Average Eggs per Female . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47 Proportion of Sexas . . . . . . . . . .c . . . . . , . . . . . . . . . . . . .i . . . . . . . . . 48 Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48 Adaptive Capacity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49 Flight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49 Feigning Death . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50 Reproduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ._ . . . . . . . . . . . . 50 Sexual Attraction and Copulation . . . . . . . . . . . . . . . . . . . . . 50 Period Between Maturity and Copulation . . . . . . . . . . . . . .. 51 PA GE Fertility . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 51 Oviposition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .' . . . . . . . . . . . 51 . Period from Emergence to Oviposition . . . . . . . . . . . .. 53: Period of Oviposition . . . . . . . . . . . . . . . . . . . . . . . . . . .. 53 Rate of Oviposition . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 54‘ Summary of Rate of Oviposition . . . . . . . . . . . . . . . . . . . 71 Broods or Generations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. Hibernation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 71 Dissemination . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72 _ Artificial Means . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 72 Natural Means . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 72 Natural Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 73 Parasites and Predacious Enemies . . . . . . . . . . . . . . . . . . . . . . . .. 73 Mortality in Diseased Tubers . . . . . . . . . . . . . . . . . . . . . . . . . .. 73 Climatic Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 73 Artificial Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 75 Quarantine Regulations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 75 Cultural Methods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 75 Clean Culture . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 75 Crop Rotation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75 Cultivation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 76 Remedial Measures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76 Weevil-free Slips or Draws . . . . . . . . . . . . . . . . . . . . . . . . . .. 76 Spraying With Arsenical Poisons. .y . . . . . . . . . . . . . . . . . . .. 76 Harvesting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 77 Storage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 77 Fumigation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 78 Summary of Control Measures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 78 Literature Cited . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .y . . . . . . . . . . . . . . 79 Bibliography . . . . . . . . . . ., . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80 Quarantine Laws, Rules, Regulations, and Interception Notices. . .. 88 ILLUSTRATIONS HGURE PAGE 1. World Distribution of the Sweet Potato Weevil . . . . . . . . . . . . .. 8 2. Distribution of the Sweet Potato Weevil in Texas . . . . . . . . . . . . . 10 3. The Sweet Potato Weevil, All Stages Shown . . . . . . . . . . . . . . . . . 14 4. Sweet Potatoes Showing Injury by the Weevil . . . . . . . . . . . . . .. 44 5. Generations of the Sweet Potato Weevil . . . . . . . . . . . . . . . . . . . . . 70 TABLES TABLE PAGE 1. Egg Measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 13 2. Duration of Egg Stage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 15 3. Yearly Variation in Duration of Egg Stage . . . . . . . . . . . . . . . . . . 22 4. Summary of Duration of Egg Stage . . . . . . . . . . . . . . . . . . . . . . . . 23 5. Duration of Larval Stage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 24 6. Yearly Variation in Duration of Larval Stage . . . . . . . . . . . . . . . 31 '7. Summary of Duration of Larval Stage . . . . . . . . . . . . . . . . . . . . .. 31 8. Measurements of Pupa . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 9. Duration of Pupal Stage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 34 10. Yearly Variation in Duration of Pupal Stage . . . . . . . . . . . . . .. 41 11. Summary of Duration of Pupal Stage . . . . . . . . . . . . . . . . . . . .. 42 12. Summary of Development of Sweet Potato Weevil . . . . . . . . . . .. 45 13. Length of Life of Adults Without Food . . . . . . . . . . . . . . . . . . . . . 46 14. Average Eggs per Female . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 47 15. Proportion of Sexes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 48 L6. Period from Emergence to Oviposition . . . . . . . . . . . . . . . . . . . . . . 52 17. Period of Oviposition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 54 18. Rate of Oviposition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55 . Summary of Rate of Oviposition . . . . . . . . . . . . . . . . . . . . . . . . . .. 69 Bulletin No. 30s . Avril, 1923 THE SWEET POTATO WEEVIL H. J. REINHARD INTRODUCTION The sweet potato weevil, Gylas formicarius Fabiz, is the most de- structive insect attacking sweet pot-atoes in Texas. For a number of years the ravages of this insect have ‘been very severe; in some sections to such an extent that the production of sweet potatoes on a com- mercial scale has been ab-andoned. The importance of this pest can- not be overestimated when it is realized that it is now permanently established in Texas, and threatens to impair seriously the sweet potato industry of the State. During the period 1916-19, inclusive, the sweet potato crop of Texas amounted to approximately 30,000,000. bushels, valued at more than $40,000,000. Any pronounced insect ravages inci- dent to this large industry must necessarily result in a great loss each year to the producers. A conservative estimate of the average annual loss in this State is 1,500,000 bushels. If the average price for the period 1916-19 is taken to be $1.10 per bushel, then the total loss for the entire period was more than $6,000,000. In addition to this direct loss to the planters, there must ‘be taken into consideration the indirect losses incurred by the failure of growers to plant a normal acreage because of the ravages caused by this weevil. There is no way of ascertaining this amount but it is doubtless a large item and must be given due consideration in estimating the extent of injury done to the sweet potato crop by this insect. This pest has become of paramount importance to the sweet potato industry in the Southern States, and has been mentioned frequently in the economic literature. The studies recorded in this Bulletin were begun by the author in January, 1918, and continued until April, 1920. HISTORY According to the available references, the sweet potato weevil was first described by Fabricius (1) as Brentus formicarius; then under the designation of Attelabus formicarim (2); and finally, again under the first name, Brentus formicarius (3). In these descriptions the insect is referred to as occurring in Tranquebar, India. The original home of the sweet potato weevil is not definitely known. It is undoubtedly of tropical origin, however, since its spread has been confined largely to tropical and semitropical regions. For many years subsequent to the appearance of the original description, the insect apparently at- tracted no attention, and was not mentioned in scientific literature. The first authentic record of it as an important enemy of sweet potatoes was made by Nietner (4) in 1857. This author in" describing the =>oo>> 3.30m 303m of Mo qoflsnmbflw 35>? A ouamwm BULLETIN N0. 308. THE SWEET POTATO WEEVIL. 9 ravages of the pest in northwestern Ceylon during the year 1856 states that in one instance practically the entire crop was destroyed. He also states that it occured throughout hundreds of acres at that time. The species was present in the United States as early as 1875, according to Le Conte and Horn (6), who reported it from New Orleans, Louisiana. These authors also recorded it from Cochin-China, India, Madagascar, and Cuba. In 1879 Comstock ('7) reported an in- festation occurring the previous year near Manatee, Florida, with the statement that it “* * * seems to threaten the destruction of the sweet potato crop of this country”. He also described the diiferent stages of the insect at that time. Riley and Howard (8) record the occurrence of the weevil in Harris County, Texas, and Price (9) in 1895 noted the pres- ence of the v/eevil at College Station, Texas. From this time to the present the insect has spread over Texas and now occurs in practically all the important sweet potato growing districts in the State. There is no very definite knowledge concerning the introduction of this pest into the United States. It was noted in Louisiana and Florida at about the same time, and only a few years later in Texas. This seems to indicate that it was introduced at several points on the Gulf Coast, from which it spread inland. Since the initial points of infesta- tion are ports of entry for the West Indies trade, it is generally con- cluded that the insect was imported from the West Indies. DISTRIBUTION _ In Figure 1 is given the world distribution of the sweet potato weevil, according to the available references on this species. It is interesting to note that its range of distribution is confined almost entirely to tropical and semitropical regions. However, the weevil is wide-spread within these latitudes, and is present on most continents and many islands. In Texas the approximate distribution is shown by the shaded portion of the map shown in Figure 2. The dots show recorded distribution by counties, and the double shaded area the region of greatest de- struction. SYSTEMATIC POSITION In his original description, Fabricius (1) placed this species in the genus Brent/us. He defined the genus as follows: Palpi inaequales, filiformcs. Amfennae moniliformes, infertae, rostro recto, porrecto, cylindrico. In 1798 Fab-ricius (2) referred it to Attelabus, and later again placed it in the former genus Brentus (3). This arrangement remained undisturbed until after the erection of the genus Oylas. Olivier, according to Le Conte and Horn (6), placed the species in the latter genus. Summers (5) in 1875 described the sweet potato weevil as Otidocepizalus elegantulus, which is quoted by Le Conteand Horn in synonomy with Cylas formicarizts. Sanderson (11) refers it to the genus Cg/las and family Oztrczrliorvidae. Comstock (12), Blatchley and Leng (13), and Le Conte and Horn (6) all list the species in the genus Cylas of the family cBrenthidae. Pierce (15) in the most recent ac- count of the systematic status of the species places it in the family Apion/idae. 10 BULLETIN N0. 308. Figure 2. Map of Iexasfshpwinflthe distribution of the sweet potato weevil. Shaded area t e approxlmate dlstnbutlon. Ileavlly shaded portion the area of greatest destructlon. "fiDots show actual records. THE SWEET POTATO WEEVIL. 11 ALLIED SPECIES According to Pierce (15) there are at least four species/floflwe vils which attack sweet potato: WaterhousefQylas form- icarius Fabricius; ’C'ylas turczgeggjfigfiBohemann; and Oylaslféinoralis Faust. Summers a sweet potato weevil as Otidocephrllus eleganturlus, which Pierce considers to be a varietal form of C. form- icarius. The species of the genus Cylas are closely related, and the fol- lowing table as given by Pierce will serve to separate the species: Table of Sweet Potato Weevils of the Genus Uylas 1. Male club» twice as long as funicle or longer; antennae as long as head and thorax; head not more than one-fifth shorter than beak; elytra greenish, thorax red, head black, legs red with dark band turcipennisBoh. Male club not twice as long as funicle . . . . . . . . . . 2. Male club half to three-fourths longer than funicle, female club almost as long as head and thorax; head one-fourth to one-third shorter than beak; elytra bluish, thorax red, head black, legs red . . . . . . . . formicarius Fabr., var. elegarntulus Summers. Male club half longer than funicle; head as long as beak; antennae as long as thorax plus head behind eye; elytra black, with blue or green luster, suture piceous; thorax black, margins piceous; head black; legs dark red with black ring .on femora . . femoralis Faust. The three species mentioned above have similar habits and pre- sumably all attack sweet potatoes, although fortunately there are no records of the occurrence of turcipennis and femoralis in this country. COMMON NAMES Since the insect has been recognized as an important enemy of sweet potatoes, it has been referred to in literature by several common names. Oomstock (7) states that the larva is known as the “sweet potato root borer”. Conradi (10) refers to the insect by the same name. Newell (14) calls it the “sweet potato root weevil”, while Chittenden (16) in the most recent important account of the insect gives it the more appropriate nanie of “sweet potato weevil”. The insect prefers feeding on the root or tuber*, but does not confine its attack to that portion of the plant. In fact, it can pass successfully a complete life cycle in the portion of the plant above ground. Since all parts of the plant are attacked, any term which specifies a particular portion subject to attack is, strictly speaking, a misnomer; therefore, the common name “sweet potato weevil” has been adopted for this insect in the present work. ECONOMIC IMPORTANCE From the time this insect was first reported an enemy of the sweet potato, its ravages have become correspondingly greater withthe growth of the. sweet potato industry. Growers frequently experience losses ranging from 20 per cent. to 5O per cent. of the entire crop in the field. ‘The sweet potato is a subterranean tuberous root, but owing to the common usage of the term “tuber” it is referred to as such in the succeeding pages. 12 BULLETIN No. 308. In some sections the weevil has been reported so abundant and de- structive in consecutive years that sweet potatoes can no longer be grown profitably as a commercial crop. The mild winter temperatures in Texas are not an effective natural check for the over-wintering weevils, and since the pest is distributed quite generally in Texas, there is hardly any one interested in the pro- duction of this crop who does not have to reckon with its ravages. N ewell estimates the annual loss at $3,500,000 for the Gulf country, which estimate other authorities consider to be conservative. About one-third of this amount is the approximate loss sustained by the Texas growers. In 1920 the sweet potato crop ranked seventh in value among the most important crops in Texas, and its future value is limited by the work of this weevil. FOOD PLANTS From the name commonly applied to this insect it might be inferred that the sweet potato is its only food plant. While it is by far its most- important food plant, the weevil feeds upon several other species of plants of the Convolvulus family, of which the morning-glory is a common example. The insect has been observed feeding on the roots of morning-glory plants collected in Brazoria County. There are about ten distinct species of I pomoea. or morning-glory which grow in the sweet potato producing sections of this State. Unfortunately, it has not been possible to make an accurate survey t0 determine the extent to which they exist, and afford a natural food plant" for the weevil. Observations show that all varieties of sweet potatoes are subject to attack. Conradi described the insect as a “general feeder” and stated that any green succulent plant will be accepted as food for the adults. However, the insect has not been observed to propagate on any plant other than sweet potato and I pomoea, and these undoubtedly constitute the natural food plants. METHODS OF STUDY Four-ounce tin salve boxes were used for making detailed observa- tions on the life history of the sweet potato weevil in the laboratory. A pair of weevils was placed in a sterilized box with a section of sweet potato tuber for oviposition, during a 24-hour period. These tubers were removed each day and a fresh supply placed with the weevils. Notations were made on the“ hatching of the daily egg quota of each female, the pupation of the larvae, and emergence of the adults. All life history observations were made in the laboratory, which was kept at ordinary room temperature. The existing temperatures were obtained by a recording thermograph, placed near the boxes containing the insect in all stages of development. Field notes were made in Brazoria and Matagorda Counties, and in the experimental plats of the Division of Entomology at College Station. ,. . l i LIFE HISTORY Former writer's have mentioned the life history of this insect in a general way. Conradi (10) gives briefly his observations on the life THE SWEET POTATO WEEvIL. 13 history, which are quoted by other writers in discussing the insect. Chittenden (16) gives additional interesting notes on the life history obtained by High in southern Texas. Our detailed observations on the life history of the insect at College Station are given in the following pages. It will be notedthat the life cycle of the sweet potato weevil is not divided into definite seasonal broods. The records show that under favorable conditions the weevils remain active and continue to breed throughout the year. Climatic conditions, however, have a posi- tive eifect on the life economy and undoubtedly restrict the abundance of the weevils at certain seasons of the year.- E99 The egg is yellowish-white, minute, broadly oval in shape, and fre- quently constricted or narrowed at the attached end. Viewed laterally it is almost uniformly convex in outline. To the unaided eye the surface appears smooth and unpolished; under the microscope it has a slightly granular appearance, but with no distinctive sculpturings. The shell is very thin, soft and fragile, and eggs exposed to light and air shrivel and dry in a short time. The size of the egg is slightly variable, which may be noted in Table 1, giving the measurement of the greatest length and width. Table 1 Egg Measurements‘; Length, Width mm. mm Average . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 0.65 0.41 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 0.65 0 45 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 0.63 O 41 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 0.65 0 44 4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 0.66 0 42 5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 0.63 0 38 6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 0.65 0 42 7 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 0.60 0 42 8 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 0.68 0 40 9 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 0.63 0 42 l0 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 0.67 0 47 11 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 0.67 0 37 12 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 0.65 O 40 13 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 0.65 0 4O 14 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 0.69 0 39 15 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 0.65 0 42 16 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 0.64 0 40 17 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 0.63 0 41 18 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 0.65 0 45 19 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 0.70 0 38 20 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 0.64 0 40 Embry0Z0gy.—The color of the egg remains unchanged as the embryonic larva increases in size. When it is nearly developed it can be detected readily through the thin egg shell. The head of the larva is directed towards the unattached end of the egg. When matured the larva begins to eat its way through the shell. Ha.tching.—Observations in most cases show that the larva emerges from the egg through the lower end, which leaves it at the beginning of feeding directed towards the interior of the tuber. However, in several instances the larva emerged through the upper end of the egg shell. The exit hole in the egg shell is always irregular and varies in size. 14 BULLETIN N0. 308. Figure 3. The sweet pot_ato weevil: l, eggs; 2, larvae; 3, pupae; 4, newly transformed adults snowlng wmgs exposed; 5, adults, female on left. males on right. THE SWEET POTATO WEEVIL. 15 The larva may begin feeding before it has entirely emerged from the egg and leave it gradually as it tunnels into the tuber, but frequently it emerges completely from the egg shell and begins feeding in the cavity. As soon as hatching begins the color of the egg turns yello , and when hatching is completed the egg is transparent and the shell very brittle. ' The length of the hatching period varies, and depends to a large extent upon existing temperatures. Under optimum conditions egggs have been observed to hatch in several hours, while in lower tempera- tures the period of hatching may extend over several days. Duration of Egg Sfifage The eggs are usually deposited in especially prepared cavities in the tubers or vines. The latter are sealed and it is impossible to make observations determining the exact length of the egg stage, Without interfering to some extent with the natural conditions. The beginning of the stage Was determined definitely by confining female weevils With uninfested tubers and noting the daily oviposition of each pair. Table 2 Duration of Egg Stage Average Temperature Lot Laid Hatched period, _ N0, days Max. Min. lWean 1918 1918 1 April 23 . . . . . . . . . . . . . . . May 5-6. . . . . . . . . . . . 12 .4 81 62 69.8 2 April 24 . . . . . . . . . . . . . .. May 6 . . . . . . . . . . . . . 12 81 62 69.8 3 April 25 . . . . . . . . . . . . . . . May 6-7 11.2 81 62 70.0 4 April 26 . . . . . . . . . . . . . . . May . . . . . . . . . . . . . 11 81 62 69.6 5 April 27 . . . . . . . . . . . . . . . May 8 . . . . . . . . . . . . . 11 86 62 70.6 6 April 28 . . . . . . . . . . . . . . . May . . . . . . . . . . . . . 11 86 62 71.3 7 April 29 . . . . . . . . . . . . . .. May 8 9 . . . . . . . . . .. 9.8 86 62 71 .6 8 April 30 . . . . . . . . . . . . . .. May 9 . . . . . . . . . . . .. 10 86 62 71 .7 9 ay 1 . . . . . . . . . . . . . .. Ma . . . . . . . . . . . .. 8 86 62 72.5 10 May 2 . . . . . . . . . . . . . . . May 9-11 7.8 92 63 75.4 11 May 3 . . . . . . . . . . . . . .. May 10 . . . . . . . . . . . .. 7 86 63 75.4 12 May 4 . . . . . . . . . . . . . .. May 11 . . . . . . . . . . . .. 7 92 63 77.3 13 May 5 . . . . . . . . . . . . . .. May 11 . . . . . . . . . . . .. 6 92 75 79.1 14 May 6 . . . . . . . . . . . . . .. May 12 . . . . . . . . . . . .. 6 92 75 81.0 15 May 7 . . . . . . . . . . . . . .. May 13 . . . . . . . . . . . .. 6 92 73 80.9 16 May 8 . . . . . . . . . . . . . . . May 1 . . . . . . . . . . . .. 7 92 73 79.8 . 17 May 9 . . . . . . . . . . . . . .. May 16 . . . . . . . . . . . .. 7 92 69 79.2 18 May 10 . . . . . . . . . . . . . .. May 17 . . . . . . . . . . . .. 7 92 69 78.5 19 May 11 . . . . . . . . . . . . . .. May 17-18 . . . . . . . . .. 7. 89 69 78.7 20 May 12 . . . . . . . . . . . . . .. May 18-19 . . . . . . . . . .. 6.1 86 69 78.3 21 May 13 . . . . . . . . . . . . . .. May 8-2 . . . . . . . . . .. 6.2 86 69, 79.0 22 May 14 . . . . . . . . . . . . . .. May . . . . . . . . . . . .. 6 86 69 79.2 23 May 15 . . . . . . . . . . . . . . . May 21 . . . . . . . . . . . .. 6 86 68 80.0 24 May 16 . . . . . . . . . . . . . .. May 22 . . . . . . . . . . . .. 6 86 74 81.0 25 May 17 . . . . . . . . . . . . . .. May . . . . . . . . . . . .. 6 86 76 81.4 26 May 18 . . . . . . . . . . . . . .. May 24 . . . . . . . . . . . .. 6 87 74 81.4 27 May 19 . . . . . . . . . . . . . .. May 25 . . . . . . . . . . . .. 6 87 74 82.0 28 May 20 . . . . . . . . . . . . . .. Ma 26 . . . . . . . . . . . .. 6 87 74 82.1 29 May 21 . . . . . . . . . . . . . . . May 26-27 5 .7 87 74 82.6 30 May 22 . . . . . . . . . . . . . . . May 27-28 . . . . . . . . . . 5.1 87 74 82.5 31 May 23 . . . . . . . . . . . . . . . May 27-28 4 .9 87 74 82.7 32 May 24 . . . . . . . . . . . . . . . May . . . . . . . . . . . . . 5 87 75 83.0 33 May 25 . . . . . . . . . . . . . . . May 30 . . . . . . . . . . . . . 5 89 75 83.1 34 May 26 . . . . . . . . . . . . . . . May 3 . . . . . . . . . . . . . 5 89 75 83.3 35 May 27 . . . . . . . . . . . . . . . une . . . . . . . . . . . . . 5 89 75 83.4 36 May 28 . . . . . . . . . . . . . . . June 3 . . . . . . . . . . . . . 6 89 77 83.9 37 May 29 . . . . . . . . . . . . . . . June 4 . . . . . . . . . . . . . 6 89 77 83.7 38 May 30 . . . . . . . . . . . . . . . June 5 . . . . . . . . . . . . . 6 89 77 83.6 39 May 31 . . . . . . . . . . . . . .. Iune 6 . . . . . . . . . . . .. 6 96 77 .3 40 June 1 . . . . . . . . . . . . . . . June 6 . . . . . . . . . . . . . 5 96 77 84.3 41 June 2 . . . . . . . . . . . . . .. June 7 . . . . . . . . . . . .. 5 97 77 86.1 42 June 3 . . . . . . . . . . . . . . . June 8 . . . . . . . . . . . . . 5 97 79 88.4 43 June 4 . . . . . . . . . . . . . .. June . . . . . . . . . . . .. 5 97 81 90.6 44 June 5 . . . . . . . . . . . . . .. June 10 . . . . . . . . . . . .. 5 97 81 92.7 45 June 6 . . . . . . . . . . . . . . . une . . . . . . . . . . . . . 6 100 87 93.5 46 June 7 . . . . . . . . . . . . . .. June . . . . . . . . . . . .. 5 100 87 93.5 47 June 8 . . . . . . . . . . . . . . . June 13 . . . . . . . . . . . . . 5 102 87, 94.2 48 June 9 . . . . . . . . . . . . . . . June . . . . . . . . . . . . . 5 102 87 94.5 16 BULLETIN N0. 308. Table 2—-Duration of Egg Stage—-Continued _ Aveg-age Temperature Lot Lald Hatched penod, No. davs Max Min. Mean 1918 49 June 10 . . . . . . . . . . . . . . . June 15 . . . . . . . . . . . . . 5 102 87 94 5O June 11 . . . . . . . . . . . . . .. June 16 . . . . . . . . . . . .. 5 102 88 94 51 June 12 . . . . . . . . . . . . . .. June 17 . . . . . . . . . . . . . 5 102 90 94 52 June 13 . . . . . . . . . . . . . . . June 18 . . . . . . . . . . . .. 5 103 89 94 53 June 14 . . . . . . . . . . . . . .. June 19 . . . . . . . . . . . .. 5 107 89 96 54 June 15 . . . . . . . . . . . . . . . June 20 . . . . . . . . . . . . . 5 107 89 96 55 June 16 . . . . . . . . . . . . . . . June 21 . . . . . . . . . . . .. 5 107 89 97 56 June 17 . . . . . . . . . . . . . . . June 22 . . . . . . . . . . . . . 5 107 89 98 57 June 18 . . . . . . . . . . . . . .. June 23 . . . . . . . . . . . . . 5 107 93 99 58 June 19 . . . . . . . . . . . . . . . June 24 . . . . . . . . . . . . . 5 105 93 98 59 June 20 . . . . . . . . . . . . . . . June 26 . . . . . . . . . . . . . 6 102 93 96 60 June 21 . . . . . . . . . . . . . . . June 26 . . . . . . . . . . . . . 5 102 93 98 61 June 22 . . . . . . . . . . . . . . . June 27 . . . . . . . . . . . . . 5 103 94 98 62 June 23 . . . . . . . . . . . . . June 28 . . . . . . . . . . . .. 5 103 94 98 63 June 24 . . . . . . . . . . . . . . . June 29 . . . . . . . . . . . . . 5 103 94 98 64 June 25 . . . . . . . . . . . . . . . June 30 . . . . . . . . . . . . . 5 103 94 98 65 June 26 . . . . . . . . . . . . . . . July 1 . . . . . . . . . . . . . . . 5 103 94 98 66 June 27 . . . . . . . . . . . . . . . July 1-2 . . . . . . . . . . . . . 4.8 103 94 98 67 June 28 . . . . . . . . . . . . . . . July 3-4 . . . . . . . . . . . . . 5.2 103 94 96 68 June 29 . . . . . . . . . . . . . . . July 4 . . . . . . . . . . . . . . . 5 102 85 96 69 June 3O . . . . . . . . . . . . . . . July . . . . . . . . . . . . . . . . 5 102 85 95 70 Dec. 17 . . . . . . . . . . . . . .. Dec 26-28 . . . . . . . . . . . 10 94 73 82 71 Dec. 18 . . . . . . . . . . . . . .. Dec 8 . . . . . . . . . . . .. 10 94 73 81 72 Dec. 19 . . . . . . . . . . . . . . . Dec‘ 29-30 . . . . . . . . . . . 10.8 94 73 82 73 Dec. 20 . . . . . . . . . . . . . . . Dec 30-Jan 1 1919. 11.2 95 73 82 74 Dec. 21 . . . . . . . . . . . . . .. Dec. 30-J1a1; 2 1919. 11.6 95 65 81 75 Dec. 22 . . . . . . . . . . . . . . . Jan 2-3 . . . . . . . . . . . . 11 95 65 80.3 76 Dec. 23 . . . . . . . . . . . . . .. Jan 3 . . . . . . . . . . . . .. 11 95 65 80.6 77 Dec. 24 . . . . . . . . . . . . . .. Jan 6-7 . . . . . . . . . . .. 13.1 95 65 79.9 78 Dec. 25 . . . . . . . . . . . . . . . Jan . . . . . . . . . . . . . . 13 95 65 79.7 79 Dec. 26 . . . . . . . . . . . . . . . Jan 7-10 . . . . . . . . . . . 13.5 95 65 78 80 Dec. 27 . . . . . . . . . . . . . .. Jan 9-11 . . . . . . . . . .. 14.1 95 65 79 81 Dec. 28 . . . . . . . . . . . . . .. Jan 10-11 . . . . . . . . . . . 14 95 65 78 82 Dec. 29 . . . . . . . . . . . . . . . Jan 11-12 . . . . . . . . . . . 14.1 95 65 79 83 Dec. 30 . . . . . . . . . . . . . . . Jan 12-15 . . . . . . . . . . . 13.9 95 65 78 84 Dec. 31. . . . . . . . . .. Jan 4-16 . . . . . . . . . .. 14 92 65 78 85 Jan 1 . . . . . . . . . . . . . . .. Ian 14-16 . . . . . . . . . .. 14.3 92 65 77. 86 Jan 2 . . . . . . . . . . . . . . .. Jan 15-17 . . . . . . . . . .. 13.6 92 67 78 87 Jan 3 . . . . . . . . . . . . . . .. Jan 16-18 . . . . . . . . . .. 14.2 92 67 78 88 Jan 4 . . . . . . . . . . . . . . .. Jan 17-18 . . . . . . . . . .. 13.8 92 67 78 89 Jan 5 . . . . . . . . . . . . . . . . Jan 18-19 . . . . . . . . . .. 13.3 92 67 79 90 Jan 6 . . . . . . . . . . . . . . .. Jan 19-20 . . . . . . . . . .. 12.9 92 67 79 91 Jan 7 . . . . . . . . . . . . . . .. an. 19-20 . . . . . . . . . .. 12.2 92 67 79 92 Jan 8 . . . . . . . . . . . . . . .. Jan 19-22 . . . . . . . . . .. 11.7 92 68 79 93 Jan 9 . . . . . . . _ . . . . . . . .. Jan 20-21 . . . . . . . . . .. 11.1 92 72 8O 94 Jan. 10 . . . . . . . . . . . . . . .. an. 0 . . . . . . . . . . . . .. 10 92 72 80 95 Jan. 11 . . . . . . . . . . . . . . .. Jan. 21-22 . . . . . . . . . .. 10.1 92 72 80 96 Jan 12 . . . . . . . . . . . . . . .. an. 2 . . . . . . . . . . . . .. 1O 92 72 79 97 Jan 13 . . . . . . . . . . . . . . .. Jan 23-24 . . . . . . . . . .. 10.3 93 72 80 98 Jan 14 . . . . . . . . . . . . . . . . Tan 24-25 . . . . . . . . . . . 10.3 93 63 79 99 Jan 15 . . . . . . . . . . . . . . .. Jan 25-28 . . . . . . . . . .. 10.8 93 63 79 100 Jan 16 . . . . . . . . . . . . . . .. Jan 26-28 . . . . . . . . . .. 10.8 93 63 79 101 Jan 17 . . . . . . . . . . . . . . .. Jan 27-29 . . . . . . . . . .. 10.2 93 63 79 102 Jan 18 . . . . . . . . . . . . . . .. Jan . . . . . . . . . . . . .. 10 93 63 79 103 Jan 19 . . . . . . . . . . . . . . .. Jan 28-29 . . . . . . . . . .. 9.6 93 63 79 104 Jan. 20 . . . . . . . . . . . . . . . . Jan 29-30 . . . . . . . . . . . 9.8 93 63 79 105 Jan. 21 . . . . . . . . . . . . . . . . Jan. 30-Feb 1 . . . . . . . 9.7 93 63 80 106 Jan. 22 . . . . . . . . . . . . . . . . an. 31-Feb. 1 . . . . . . . 9.2 93 63 80 107 Jan. 23 . . . . . . . . . . . . . . .. Jan 31-Feb. 6 . . . . . .. 9.4 93 63 78 108 Jan. 24 . . . . . . . . . . . . . . . . Feb. 2-5 . . . . . . . . . . . . 9.8 93 63 78 109 Jan. 25 . . . . . . . . . . . . . . .. Feb. 5-6 . . . . . . . . . . .. 11.1 93 63 78 110 Jan. 26 . . . . . . . . . . . . . . . . Feb. 7 . . . . . . . . . . . .. 12 93 65 79 111 Jan. 27 . . . . . . . . . . . . . . .. Feb. 7-8 . . . . . . . . . . .. 11.1 93 65 79 112 Jan. 28 . . . . . . . . . . . . . . .. Feb. 8-9 . . . . . . . . . . .. 11.7 93 65 79 113 Jan. 29 . . . . . . . . . . . . . . . . Feb. 9-13 . . . . . . . . . .. 12.1 93 65 79 114 Jan. 30 . . . . . . . . . . . . . . .. Feb 11-12 . . . . . . . . . .. 12.1 93 65 78 115 Jan. 31 . . . . . . . . . . . . . . .. Feb 12-13 . . . . . . . . . .. 12.2 89 65 78 116 Feb. 1 . . . . . . . . . . . . . .. Feb 1 . . . . . . . . . . . . . 12 89 b 65 78 117 Feb. 2 . . . . . . . . . . . . . .. Feb 13-14 . . . . . . . . . .. 11 93 65 78 118 Feb. 3 . . . . . . . . . . . . . .. Feb 13-14 . . . . . . . . . .. 10.1 93 65 79 119 Feb. 4.. Feb 14-15 . . . . . . . . . .. 10.2 93 65 80 120 Feb. 5 . . . . . . . . . . . . .. Feb 14-16 . . . . . . . . . . . 9.8 93 65 80 121 Feb. 6 . . . . . . . . . . . . . . . Feb , . . . . . . . . . . . . 10 93 65 80 122 Feb. 7 . . . . . . . . . . . . . .. Feb 1 . . . . . . . . . . . .. 10 93 65 80 123 Feb. 8 . . . . . . . . . . . . . .. Feb 17-18 . . . . . . . . . .. 9 93 65 80 124 Feb. 9 . . . . . . . . . . . . . .. Feb. 18-19 . . . . . . . . . . . 8.9 93 65 80 125 Feb 10 . . . . . . . . . . . . . .. Feb. 19-20 . . . . . . . . . .. 8.7 93 65 80 126 Feb 11 . . . . . . . . . . . . . . . Feb. 19-20 . . . . . . . . . .. 8.1 93 70 81 éL-Z-Z»iobok-kzbkzinbobvkrlebbobinlzboL-alobl: THE SWEET POTATO WEEVIL. 17 Table 2—-Durati0n of Egg Stage-Continued _ Average Temperature Lot Laid Hatched period, _ No. days Max. Min. Mean 1919 127 Feb. 12 . . . . . . . . . . . . . .. Feb. 20-21 . . . . . . . . . .. 8.2 93 7O 81.3 128 Feb.13 . . . . . . . . . . . . . ..Feb 9 93 63 80.3 129 Feb. 14 . . . . . . . . . . . . . . . Feb 23-24 . . . . . . . . . . . 8.9 93 63 78.6 130 Feb. 15 . . . . . . . . . . . . . . . Feb 24-25 . . . . . . . . . . . 9.3 93 63 78.9 131 Feb. 16 . . . . . . . . . . . . . . . Feb. 25-26 . . . . . . . . . . . 9.2 93 63 79.0 132 Feb. 17 . . . . . . . . . . . . . . . Feb. 26-27 . . . . . . . . . . . 9.2 90 63 78.8 133 Feb. 18 . . . . . . . . . . . . . .. Feb. 27-March 1. . . .. 10.5 90 63 79.0 134 Feb. 19 . . . . . . . . . . . . . . . March 1-2 . . . . . . . . . . 10.4 90 63 80.4 135 Feb. 20 . . . . . . . . . . . . . . . March 4-8 . . . . . . . . . . 12 95 63 80.3 136 Feb. 21 . . . . . . . . . . . . . .. March 4... 11 101 63 81.6 137 Feb 22 . . . . . . . . . . . . . .. March 4-6 . . . . . . . . .. 11.2 101 71 83.1 138 Feb. 23 . . . . . . . . . . . . . .. March 6-7 . . . . . . . . . . 11.6 101 71 83 .5 139 Feb 24 . . . . . . . . . . . . . .. March 7-8 . . . . . . . . .. 11.3 101 74 84.3 140 Feb. 25 . . . . . . . . . . . . . . . March 7-8 . . . . . . . . . . 11.4 101 74 84 .5 141 Feb. 26 . . . . . . . . . . . . . . . March 8-9 . . . . . . . . . . 11.2 101 73 83.9 142 Feb.27 . . . . . . . . . . . . . ..March 10 101 73 84.1 143 Feb. 28 . . . . . . . . . . . . . .. March 10. . . . . . . . . . .. 10 101 72 83 .4 144 March . . . . . . . . . . . . .. March 11-14 . . . . . . . .. 10.3 101 72 82.6 145 March 2 . . . . . . . . . . . . .. March 12 ........ 9.6 101 72 83.3 146 March 3 . . . . . . . . . . . . . March 12-13 . . . . . . . . . 9 101 72 82.0 147 March 4 . . . . . . . . . . . . . . March 14-16 . . . . . . . . . 10.5 98 72 81.0 148 March 5 . . . . . . . . . . . . .. March 15-16 . . . . . . . .. 10.1 90 72 80.2 149 March 6 . . . . . . . . . . . . .. March 16-17 . . . . . . . .. 10.2 90 72 80.1 150 March 7 . . . . . . . . . . . . .. March 17- 9 . . . . . . . .. 10.8 86 72 79.1 151 March 8 . . . . . . . . . . . . .. March 18-19 . . . . . . . .. 11.2 86 72 78.7 152 March . . . . . . . . . . . . . March 19-20 . . . . . . . . . 11 .6 86 72 78.7 153 March 10 . . . . . . . . . . . . . . March 20-22 . . . . . . . . . 11 86 71 79.2 154 ‘VIarch 11 . . . . . . . . . . . . .. March 22-23 . . . . . . . . . 11.5 86 71 79.2 155 March 12 . . . . . . . . . . . . .. March 22-24 . . . . . . . . . 11.1 86 71 79.0 156 Vlarch 13 . . . . . . . . . . . . . . March 24-25 . . . . . . . . . 11 86 71 79.2 157 March 14 . . . . . . . . . . . . .. March 25 ........ 11 86 71 79.0 158 March 15 . . . . . . . . . . . . . . March 25-26 . . . . . . . . . 11.3 86 71 78.6 159 March 16 . . . . . . . . . . . .. March 26-27 . . . . . . . .. 11.5 86 71 77.9 160 March 17 . . . . . . . . . . . . .. March 28 . . . . . . . . . . .. 11 86 71 77.9 161 March 18 . . . . . . . . . . . . .. March 29-30 . . . . . . . .. 11.8 88 71 78.3 162 March 19 . . . . . . . . . . . . .. March 31-April 1.. . .. 12.5 88 71 78.8 163 . March 20 . . . . . . . . . . . . .. March 30-April 1.. . . . 11.8 88 71 78.9 164 March 21 . . . . . . . . . . . . . . April 2 . . . . . . . . . . . . . 12 88 71 79.0 165 March 22 . . . . . . . . . . . . . . April 3 . . . . . . . . . . . . . 12 88 71 78.5 166 March 23 . . . . . . . . . . . . .. April 3-4 . . . . . . . . . . . 11. 88 71 78.5 167 March 24 . . . . . . . . . . . . . . April 4-5 . . . . . . . . . . . 11 88 71 78.6 168 March 25 . . . . . . . . . . . . . . April 5-6 . . . . . . . . . . . 11.5 88 71 ‘ 78.7 169 March 26 . . . . . . . . . . . . . . April 6 . . . . . . . . . . . . . 11 88 71 78.8 170 March 27 . . . . . . . . . . . . . April 7 . . . . . . . . . . . . . 11 88 72 79 .6 171 Marrh 28 . . . . . . . . . . . . . . April 8 . . . . . . . . . . . . . 11 88 73 80.2 172 March 29 . . . . . . . . . . . . . . April 9 . . . . . . . . . . . . . 11 88 73 79.9 173 Vlarch 30 . . . . . . . . . . . . . . April 1O . . . . . . . . . . . . . 11 88 71 80.3 174 March 31 . . . . . . . . . . . . .. April 10-11 . . . . . . . . .. 10.2 88 70 80.2 175 April 1 . . . . . . . . . . . . . .. April 11-12 . . . . . . . . .. 10.4 90 70 80.3 176 April 2 . . . . . . . . . . . . . . . April 12-13 . . . . . . . . . . 10.6 93 70 80.0 177 April 3 . . . . . . . . . . . . . . . April 13 . . . . . . . . . . . . . 10 93 70 81.4 178 April 4 . . . . . . . . . . . . . . . April 14 . . . . . . . . . . . . . 10 95 70 82.2 179 April 5 . . . . . . . . . . . . . . . April 15 . . . . . . . . . . . . . 10 95 70 82.7 180 April 6 . . . . . . . . . . . . . . . April 16 . . . . . . . . . . . . . 10 95 70 83.3 181 April 7 . . . . . . . . . . . . . . . April 17 . . . . . . . . . . . . . 10 95 70 83.0 182 April 8 . . . . . . . . . . . . . . . April 18 . . . . . . . . . . . . . 10 95 70 82.5 183 April 9 . . . . . . . . . . . . . . . April'19-20 . . . . . . . . . . 10.2 95 70 82.7 184 April 10. . . . .' . . . . . . . . . . April 20-21 . . . . . . . . . . 10.6 95 70 83.2 185 April 11 . . . . . . . . . . . . . . . April 22 . . . . . . . . . . . . . 11 95 72 83.7 186 April 1 . . . . . . . . . . . . . . . April 23 . . . . . . . . . . . . . 11 95 72 83 .9 187 April 13 . . . . . . . . . . . . . . . April 23-24 . . . . . . . . . . 11.2 95 72 83 .9 188 April 14 . . . . . . . . . . . . . . . April 24-25 . . . . . . . . . . 10.3 92 72 83.5 189 pril 1 . . . . . . . . . . . . . . . April 25-26 . . . . . . . . . . 10.6 92 72 83.6 190 April 16 . . . . . . . . . . . . . . . April 25 ~26 . . . . . . . . . . 9 .7 90 72 83 .4 191 April 17 . . . . . . . . . . . . . . . April 26-27 . . . . . . . . . . 9.5 90 75 83.7 192 April 18 . . . . . . . . . . . . . . . April 27-28 . . . . . . . . . . 9.1 93 77 84.5 193 April 19 . . . . . . . . . . . . . . . April 28 . . . . . . . . . . . . . 9 93 77 84 .6 194 April 20 . . . . . . . . . . . . . . . April 28-29 . . . . . . . . . . 8 .5 93 77 84.8 195 April 21 . . . . . . . . . . . . . . . April 29 . . . . . . . . . . . . . 8 93 77 84.9 196 April 22 . . . . . . . . . . . . . . . April 30-May 1 . . . . . . 8.2 93 76 84.6 197 April 23 . . . . . . . . . . . . . . . ‘VI ay 1 . . . . . . . . . . . . . 8 93 76 84 .7 198 April 24 . . . . . . . . . . . . . . . May . . . . . . . . . . . . . 8 93 76 84.8 199 April 25 . . . . . . . . . . . . . . . May 3-4.. 8.1 93 76 85.5 200 April 26 . . . . . . . . . . . . . . . May 4 . . . . . . . . . . . . . 8 93 76 85.5 201 April 27 . . . . . . . . . . . . . . . May 5 . . . . . . . . . . . . . 8 93 76 86.2 202 April 28 . . . . . . . . . . . . . . . May 6 . . . . . . . . . . . . . 8 93 76 85.9 203 April 29 . . . . . . . . . . . . . . . May 7 . . . . . . . . . . . . . 8 93 75 85.0 204 April 30 . . . . . . . . . . . . . . . May 8 . . . . . . . . . . . . . 8 93 75 84.6 205 May 1 . . . . . . . . . . . . . .. May 9 . . . . . . . . . . . . . 8 93 75 84.0 18 BULLETIN N0. 308. Table 2- Duration of EggfStage——Continued _ Aveyage Temperature Lot La1d Hatched penod, No. ays Max. Min. Mean 1919 206 May 2 . . . . . . . . . . . . . .. May 10 . . . . . . . . . . . .. 8 92 75 82.6 207 May 3 . . . . . . . . . . . . . .. ‘Vlay 11-12 . . . . . . . . .. 8.4 90 71 80.6 208 May 4 . . . . . . . . . . . . . . . May 12-13 8.7 90 71 80.3 209 May 5 . . . . . . . . . . . . . .. May 14 . . . . . . . . . . . .. 9 94 71 80.5 210 May 6 . . . . . . . . . . . . . .. May 15-16 . . . . . . . . .. 9.8 94 71 80.7 211 May 7 . . . . . . . . . . . . . .. . ay 18 . . . . . . . . . . . .. 1 100 71 82.8 212 May 8 . . . . . . . . . . . . . .. May 18 . . . . . . . . . . . .. O 100 71 83.2 213 May 9 . . . . . . . . . . . . . .. May 18 . . . . . . . . . . . .. 9 100 71 85.0 214 May 1O . . . . . . . . . . . . . .. May 19 . . . . . . . . . . . .. 9 100 71 86.3 215 May 11 . . . . . . . . . . . . . .. May 19-20 . . . . . . . . . .. 8.7 100 75 87.4 216 May 12 . . . . . . . . . . . . . .. May 20-21 8.4 100 75 88.0 217 ay 13 . . . . . . . . . . . . . .. ay 21 . . . . . . . . . . . .. 8 100 76 88.7 218 May 14 . . _ . . . . . . . . . . .. May 22 . . . . . . . . . . . . . 8 100 76 88.0 219 May 15 . . , . . . . . . . . . . .. May 23 . . . . . . . . . . . .. 8 lOO 76 88.0 220 ay 16 . . . . . . . . . . . . . .. May 24 . . . . . . . . . . . .. 8 100 76 87.0 221 May 17 . . . . . . . . . . . . . .. ay 25 . . . . . . . . . . . . . 8 98 76 86.0 222 May 18 . . . . . . . . . . . . . . . May 26 . . . . . . . . . . . . . 8 93 76 85.4 223 May 19 . . . . . . . . . . . . . . . May 26-27 . . . . . . . . . . 7.3 93 76 84.8 224 May 2O . . . . . . . . . . . . . . . ay 28 . . . . . . . . . . . . . 8 93 76 85.2 225 May 21 . . . . . . . . . . . . . .. May 29 . . . . . . . . . . . .. 8 94 4 77 85.3 226 ay 22 . . . . . . . . . . . . . . . May 30-31 8.8 94 76 85.1 227 May 23 . . . . . . . . . . . . . . . ay 31 . . . . . . . . . . . . . 8 94 76 85.0 228 May 24 . . . . . . . . . . . . . . . June . . . . . . . . . . . . . 8 94 76 84.9 229 ay 25 . . . . . . . . . . . . . .. June 1-2.. 7.8 94 76 85.3 230 May 26 . . . . . . . . . . . . . .. June 2 . . . . . . . . . . . .. 7 94 76 85.5 231 ay 27 . . . . . . . . . . . . . .. June 3 . . . . . . . . . . . .. 7 94 76 85.5 232 May 28 . . . . . . . . . . . . . . . June 4 . . . . . . . . . . . . . 7 93 76 84.3 233 May 29 . . . . . . . . . . . . . . . June 5 . . . . . . . . . . . . . 7 93 76 83.7 234 May 30 . . . . . . . . . . . . . . . June 7 . . . . . . . . . . . . . 8 93 76 83.6 235 May 31 . . . . . . . . . . . . . .. June 8 . . . . . . . . . . . .. 8 100 77 84.8 236 June 1 . . . . . . . . . . . . . .. June 9 . . . . . . . . . . . .. 8 101 77 86.2 237 June 2 . . . . . . . . . . . . . .. June 10 . . . . . . . . . . . .. 8 101 77 85.8 238 June 3 . . . . . . . . . . . . . .. une 1O . . . . . . . . . . . .. 7 101 80 86.2 239 June 4 . . . . . . . . . . . . . .. June 11 . . . . . . . . . . . .. 7 101 76 86.6 240 June 5 . . . . . . . . . . . . . .. June 11 . . . . . . . . . . . .. 6 101 76 87.7 241 June 6 . . . . . . . . . . . . . .. June 12 . . . . . . . . . . . .. 6 101 76 88.9 242 June 7 . . . . . . . . . . . . . .. June 13-14 . . . . . . . . . . 6.3 101 76 '89.7 243 June 8 . . . . . . . . . . . . . .. June 14 . . . . . . . . . . . .. 6 101 76 89.2 244 June 9 . . . . . . . . . . . . . .. June 15 . . . . . . . . . . . .. 6 96 76 88.0 245 June 1 . . . . . . . . . . . . . .. June 15-17 . . . . . . . . .. 6.7 96 76 87.2 246 June 11 . . . . . . . . . . . . . .. June 17-18 . . . . . . . . .. 6.2 96 8O 88.1 247 June 12 . . . . . . . . . . . . . . . 7 95 8O 88.0 7 95 8O 88.0 7 94 80 88.0 7.1 94 8O 87.7 6 94 81' 88.7 6.3 94 81 88.7 7 94 81 88.6 7 94 81 88.4 7.3 94 81 88.2 7.6 93 81 . 88.2 6.2 93 83 - 88.5 6.4 95 84 89. 1 6 95 84 89.1 6 96 84 89.7 6 96 84 90.7 6 96 84 90. 1 6 96 87 91.0 . 6 96 88 90.2 6.7 97 89 90.8 6.8 97 85 89.9 7 98 85 90.9 5.7 100 85 92.2 6 100 85 91.5 6 lOO 85 93.2 6 lOO 85 93.8 6 100 85 94.7 6 100 9O 96.2 6.7 lOO 9O 94.6 6.2 101 91 93.5 6.5 101 90 93. 1 6.1 101 87 92.3 6.1 101 87 91 .8 6 101 87 90.6 5.1 101 87 90.8 5 101 87 91 .8 282 July 17 . . . . . . . . . . . . . . . . July 22 . . . . . . . . . . . . . . 5 96 87 93.2 283 uly 18 . . . . . . . . . . . . . . . . July 23-24 . . . . . . . . . . . 5.6 96 86 92.0 THE SWEET Porno WEEVIL. 19 Table 2—-—Duration of Egg Stage-Continued A Average Temperature Lot Laid Hatched penod, _ N0. days Max Mm. Mean 1919 284 July 19 . . . . . . . . . . . . . . . . July 24-25 . . . . . . . . . . . 5.5 96 86 92.0 285 July 20 . . . . . . . . . . . . . . . . July 25-26 . . . . . . . . . . . . 5.5 97 86 91 .8 286 July 21 . . . . . . . . . . . . . . . . July 26 . . . . . . . . . . . . . . 5 97 86 91 .3 287 July 22 . . . . . . . . . . . . . . .. July 27-28 . . . . . . . . . .. 5.5 97 85 91.0 288 July 23 . . . . . . . . . . . . . . . . July 28-29 . . . . . . . . . . . 5.3 97 85 91 .5 289 July 24 . . . . . . . . . . . . . . . . July 29-30 . . . . . . . . . . . 5.4 98 85 92.5 290 July 25 . . . . . . . . . . . . . . . . July 30 . . . . . . . . . . . . . . 5 98 85 92.8 291 July 26 . . . . . . . . . . . . . . .. July 31 . . . . . . . . . . . . .. 5 98 85 93.1 292 July 27 . . . . . . . . . . . . . . . . Aug. . . . . . . . . . . . . . 5 98 85 93.4 293 July 28 . . . . . . . . . . . . . . . . Aug. . . . . . . . . . . . . . 5 98 91 94.3 294 July 29 . . . . . . . . . . . . . . . . Aug. 3-4 . . . . . . . . . . . . 5.3 98 90 94.2 295 July 3O . . . . . . . . . . . . . . . . Aug. 4 . . . . . . . . . . . . . 5 97 90 94.2 296 July 31 . . . . . . . . . . . . . . . . Aug 5 . . . . . . . . . . . . . 5 97 90 94.2 297 Aug. 1 . . . . . . . . . . . . . . . Aug 6 . . . . . . . . . . . . . 5 97 90 94.1 298 Aug. 2 . . . . . . . . . . . . . . . Aug 7 . . . . . . . . . . . . . 5 - 97 9O 93.8 299 Aug. 3 . . . . . . . . . . . . . . . Aug. 8 . . . . . . . . . . . . . 5 97 9O 93.9 300 Aug. 4 . . . . . . . . . . . . . . . Aug. 9 . . . . . . . . . . . . . 5 98 90 93.8 301 Aug. 5 . . . . . . . . . . . . . . . Aug. 10 . . . . . . . . . . . . . 5 98 90 93.6 302 Aug. 6 . . . . . . . . . . . . . . . Aug. 11 . . . . . . . . . . . . . 5 98 90 93.8 303 Aug. 7 . . . . . . . . . . . . . . . Aug. 12 . . . . . . . . . . . . . 5 98 88 93.0 304 Aug. 8 . . . . . . . . . . . . . . . Aug. 13 . . . . . . . . . . . . . 5 98 88 92.5 305 Aug. 9 . . . . . . . . . . . . . . . Aug. 14 . . . . . . . . . . . . . 5 97 88 92.0 306 Aug. 10 . . . . . . . . . . . . . . . Aug. 15 . . . . . . . . . . . . . 5 95 88 91 .-8 307 Aug. 11 . . . . . . . . . . . . . .. Aug. 16 . . . . . . . . . . . .. 5 95 88 91 .5 308 Aug. 12 . . . . . . . . . . . . . . . Aug. 18 . . . . . . . . . . . . . 6 95 88 92.0 309 Aug. 13 . . . . . . . . . . . . . . . Aug. 19 . . . . . . . . . . . . . 6 95 85 91 .8 310 Aug. 14 . . . . . . . . . . . . . . . Aug. 20 . . . . . . . . . . . . . 6 95 85 91 .5 311 Aug. 15 . . . . . . . . . . . . . .. Aug. 21 . . . . . . . . . . . .. 6 95 85 90.7 312 Aug. 16 . . . . . . . . . . . . . . . Aug. 22 . . . . . . . . . . . . . 6 95 84 89.8 313 Aug. 17 . . . . . . . . . . . . . .. Aug. 22-23 5.7 95 81 . 88.3 314 Aug. 18 . . . . . . . . . . . . . . . Aug. 23-24 . . . . . . . . . . . 5.2 95 81 87.2 315 Aug. 19 . . . . . . . . . . . . . . . Aug. 25 . . . . . . . . . . . . . 6 92 81 86.7 316 Aug. 2O . . . . . . . . . . . . . .. Aug. 26 . . . . . . . . . . . . . 6 91 80 86.0 317 Aug. 21 . . . . . . . . . . . . . .. Aug. 27 . . . . . . . . . . . .. 6 91 80 85.7 318 Aug. 22 . . . . . . . . . . . . . . . Aug. 28 . . . . . . . . . . . . . 6 91 80 85.9 319 Aug. 23 . . . . . . . . . . . . . . . Aug. 29 . . . . . . . . . . . . . 6 93 80 87. 1 320 Aug. 24 . . . . . . . . . . . . . . . Aug 29-30 . . . . . . . . . . 5.2 94 80 88. 1 321 Aug. 25 . . . . . . . . . . . . . . . Aug 0 . . . . . . . . . . . . . 5 94 80 88.3 322 Aug. 26 . . . . . . . . . . . . . . . Sept 1 . . . . . . . . . . . . . 6 95 82 89.5 323 Aug._27 . . . . . . . . . . . . . . . Sept 2 . . . . . . . . . . . . . 6 95 78 89.1 324 Aug. 28 . . . . . . . . . . . . . . . Sept. 3 . . . . . . . . . . . . . 6 95 77 88.1 325 Aug. 29 . . . . . . . . . . . . . . . Sept. 4 . . . . . . . . . . . . . 6 95 77 86.9 326 Aug. 30 . . . . . . . . . . . . . . . Sept. 5 . . . . . . . . . . . . . g6 95 77 85.7 327 Aug. 31 . . . . . . . . . . . . . . . Sept 6-7 . . . . . . . . . . . 6.7 95 77 84.4 328 Sept. 1 . . . . . . . . . . . . . .. Sept. 8 . . . . . . . . . . . .. 7 9O 77 83.6 329 Sept. 2 . . . . . . . . . . . . . .. Sept. 9 . . . . . . . . . . . .. 7 90 77 _ 84.0 330 Sept. 3 . . . . . . . . . . . . . . . Sept. 11 . . . . . . . . . . . . . 8 95 80 85.9 331 Sept. 4 . . . . . . . . . . . . . .. Sept 12 . . . . . . . . . . . .. 8 96 80 87.0 332 Sept 5 . . . . . . . . . . . . . . . Sept. 13 . . . . . . . . . . . . . 8 97 80 87.5 333 Sept. 6 . . . . . . . . . . . . . . . Sept. 14-16 . . . . . . . . . . 8.5 97 77 87.1 334 Sept. 7 . . . . . . . . . . . . . . . Sept. 16 . . . . . . . . . . . . . 9 97 77 87.6 335 Sept. 8 . . . . . . . . . . . . . . . Sept. 17 . . . . . . . . . . . . . 9 97 77 87.6 336 Sept. 9 . . . . . . . . . . . . . . . Sept. 18 . . . . . . . . . . . . . 9 97 77 87.4 337 Sept. 10 . . . . . . . . . . . . . . . Sept. 19 . . . . . . . . . . . . . 9 97 77 87.2 338 Sept. 11 . . . . . . . . . . . . . . . Sept. 20-22 . . . . . . . . . . 9.5 97 77 87.0 339 Sept. 12 . . . . . . . . . . . . . . . Sept 21-22 . . . . . . . . . . 9.2 97 77 86.4 340 Sept. 13 . . . . . . . . . . . . . . . Sept . . . . . . . . . . . . . 9 92 77 86.4 *341 Sept. 14 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . *342 Sept. 15 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 343 Sept. 16 . . . . . . . . . . . . . . . Sept. 23 . . . . . . . . . . . . . 7 91 76 86.1 344 Sept. 17 . . . . . . . . . . . . . . . Sept. 24 . . . . . . . . . . . . . 7 91 75 84.8 345 Sept. 18 . . . . . . . . . . . . . . . Sept. 25-26 . . . . . . . . . . 7.2 91 74 83. 1 346 Sept. 19 . . . . . . . . . . . . . . . Sept. 27 . . . . . . . . . . . . . 8 91 74 82.0 347 Sept. 20 . . . . . . . . . . . . . . . Sept. 28 . . . . . . . . . . . . . 8 89 74 81 .6 348 Sept 21 . . . . . . . . . . . . . . . Sept. 29 . . . . . . . . . . . . . 8 92 74 81 .6 349 Sept. 22 . . . . . . . . . . . . . . . Sept. 30 . . . . . . . . . . . . . 8 96 74 81 .6 350 Sept. 23 . . . . . . . . . . . . . . . Oct. 1-2 . . . . . . . . . . . . 8.8 96 74 83.1 351 Sept. 24 . . . . . . . . . . . . . . . Oct. 2 . . . . . . . . . . . . . . 8 96 74 84.0 352 Sept. 25 . . . . . . . . . . . . . . . Oct. 3 . . . . . . . . . . . . . . 8 96 75 84.8 353 Sept. 26 . . . . . . . . . . . . . . . Oct. 4 . . . . . . . . . . . . . . 8 96 75 86.0 354 Sept. 27 . . . . . . . . . . . . . . . Oct. 5 . . . . . . . . . . . . . . 8 96 80 87.0 355 Sept. 28 . . . . . . . . . . . . . . . Oct. 6 . . . . . . . . . . . . . 8 96 80 87.2 356 Sept. 29 . . . . . . . . . . . . . . . Oct. 7 . . . . . . . . . . . . . . 8 96 80 86.6 357 Sept. 3O . . . . . . . . . . . . . . . Oct. 7-8 . . . . . . . . . . . . 8.3 94 80 86.3 358 Oct. 1 . . . . . . . . . . . . . . .. Oct. 9-10 . . . . . . . . . .. 8.9 94 80 86.6 359 Oct. 2 . . . . . . . . . . . . . . . . Oct. 10 . . . . . . . . . . . . . . 8 93 80 96.3 360 Oct. 3 . . . . . . . . . . . . . . . . Oct 11 . . . . . . . . . . . . . . 8 93 78 86.1 361 Oct. 4 . . . . . . . . . . . . . . .. Oct 12 . . . . . . . . . . . . .. 8 93 75 84.8 *1 ncomplete record. 20 BULLETIN N0. 308. Table 2—-Duration 0f Egg Stage——Continued Average Temperature Lot Laid Hatched period, _ PJO. days h4ax hdln. h4ean 362 8 91 74 83.2 363 8.8 91 74 81.0 364 8.2 91 74 80.8 365 9.1 91 69 78.9 366 9.6 91 69 77.4 367 10 88 69 75.9 368 10 88 69 75.5 369 10 84 69 75.9 370 10 87 69 76.9 371 10 90 69 78.2 372 9.3 90 69 79.3 373 9.5 90 69 80.1 374 10 90 69 81.1 375 10 90 70 82.5 376 9.5 90 72 83.1 377 9.1 90 73 83.3 378 9 90 73 83.9 379 9 90 73 83.9 380 8.3 90 73 83.5 381 8.8 90 73 82.2 382 9 90 73 80.7 383 8. 90 73 80.0 384 8 90 73 78.4 385 8 87 -72 77.2 386 8 87 72 77.1 387 8 87 72 77.6 388 8 88 72 77.7 389 8 94 72 78.4 390 8 94 72 79.7 391 7 94 72 80.6 392 7 94 72 81.2 393 7 94 74 81.5 394 7 94 74 81.6 395 7 94 66 80.8 396 7 94 66 80.4 397 7 92 66 80.0 398 7 84 66 78.0 399 8.6 83 66 78.1 400 9 83 66 78.2 401 9 84 66 78.6 402 10 86 75 80.0 403 9 87 75 80.1 404 9 88 75 81.0 405 8.8 89 75 81.7 406 8 89 75 82.0 407 9 89 69 80.3 408 9.3 89 66 79.2 409 10 89 66 78.2 410 10 89 66 77.4 411 10 89 64 76.0 412 10 89 64 74.6 413 9.8 89 64 73.6 414 9 80 64 72.3 415 9 88 64 72.9 416 8.8 94 64 74.7 417 8 94 64 74.9 418 8 94 64 75.9 419 9 94 64 77.2 420 9 94 64 77.3 421 9 94 65 78.7 422 9 94 60 78.5 423 9 94 60 78.0 424 9 94 60 76.0 425 9 91 60 74.0 426 10 91 60 74.4 427 9 89 60 73.5 428 9 93 60 74.5 429 9 93 60 75.7 430 10 93 V60 76.2 431 10 93 63 77.1 432 10 93 63 78.1 433 11 93 56 78.0 434 13 93 56 78.8 435 13 93 56 79.1 436 13 93 56 79.4 437 14 93 56 79.3 438 14 88 56 78.7 439 14 88 56 78.6 THE SWEET POTATO WEEVIL. 21 Table 2—Durati0n of Egg Stage——Continued Average Temperature Laid Hatched period, ‘ days Max. Min. Mean 1919 Dec. 22 . . . . . . . . . . . . . . . Jan 5-6 . . . . . . . . . . . . 14.5 88 56 77.9 Dec. 23 . . . . . . . . . . . . . .. Jan 7 . . . . . . . . . . . . .. 15 88 56 77.7 Dec 26 . . . . . . . . . . . . . .. Jan 8 . . . . . . . . . . . . .. 13 88 71 78.7 Dec 29 . . . . . . . . . . . . . .. Jan 11 . . . . . . . . . . . . .. 13 88 71 78.2 Dec 3O . . . . . . . . . . . . . .. Ian 12 . . . . . . . . . . . . .. 13 88 71 77.8 Dec 3 Jan 13 . . . . . . . . . . . . .. 13 88 71 77.6 1920 Jan. . . . . . . . . . . . . . . .. Jan. 14 . . . . . . . . . . . . .. 9 93 71 77.6 Jan. 6 . . . . . . . . . . . . . . .. Jan. 15 . . . . . . . . . . . . .. 9 93 72 78.7 Jan. 7 . . . . . . . . . . . . . . .. Jan. 16 . . . . . . . . . . . . .. 9 95 72 79.8 Jan. 8 . . . . . . . . . . . . . . .. Jan. 17 . . . . . . . . . . . . .. 9 96 72 81.1 Jan. 9 . . . . . . . . . . . . . . .. Jan. 18 . . . . . . . . . . . . .. 9 96 74 82.4 Jan. 10 . . . . . . . . . . . . . . .. Jan. 19 . . . . . . . . . . . . .. 9 96 74 82.7 Jan. 11 . . . . . . . . . . . . . . .. Jan. 2O . . . . . . . . . . . . .. 9 96 74 ' 84.3 Jan. 12 . . . . . . . . . . . . . . .. Jan. 2 . . . . . . . . . . . . .. 9 96 74 85.2 Jan. 13 . . . . . . . . . . . . . . .. Jan. 22-23 . . . . . . . . . .. 9.2 96 70 83.7 Jan. 14 . . . . . . . . . . . . . . .. Jan. . . . . . . . . . . . . .. 1O 96 7O 83.5 lan.15 . . . . . . . . . . . . . . .. Jan. 26 . . . . . . . . . . . . .. 11 96 7O 81.8 Jan. 16 . . . . . . . . . . . . . . .. Jan. 27 . . . . . . . . . . . . .. 11 96 70 81.0 Jan. 19 . . . . . . . . . . . . . . .. Jan. 28 . . . . . . . . . . . . .. 6 90 70 78.2 Jan. 20 . . . . . . . . . . . . . . . . Jan. 30 . . . . . . . . . . . .. 10 90 64 76.7 Jan. 21 . . . . . . . . . . . . . . .. Jan. 31 . . . . . . . . . . . . . . 10 87 64 76.1 Jan. 22 . . . . . . . . . . . . . . .. Feb 1 . . . . . . . . . . . .. 10 91 64 76.9 Jan. 23 . . . . . . . . . . . . . . .. Feb 2 . . . . . . . . . . . .. 10 93 64 77.4 Jan. 24 . . . . . . . . . . . . . . .. Feb 3 . . . . . . . . . . . .. 10 95 64 78.1 Jan. 25 . . . . . . . . . . . . . . .. Feb 4 . . . . . . . . . . . .. 10 95 64 78.8 Ian. 26 . . . . . . . . . . . . . . .. Feb 5 . . . . . . . . . . . .. 1O 95 64 79.4 Ian. 27 . . . . . . . . . . . . . . .. Feb 6 . . . . . . . . . . . . . 10 95 64 79.8 Jan. 28 . . . . . . . . . . . . . . .. Feb 7 . . . . . . . . . . . .. 10 95 64 80.5 Ian. 29 . . . . . . . . . . . . . . . . Feb 8 10 95 64 80.5 Jan. 30 . . . . . . . . . . . . . . .. Feb . . . . . . . . . . . .. 1O 95 70 80.9 Jan. 31 . . . . . . . . . . . . . . .. Feb 10 . . . . . . . . . . . .. 1O 95 7O 80.5 Feb. 1 . . . . . . . . . . . . . .. Feb 11 . . . . . . . . . . . .. 10 95 68 79.9 Feb. 2 . . . . . . . . . . . . . . . Feb . . . . . . . . . . . . . 10 95 68 79.2 Feb. 3 . . . . . . . . . . . . . .. Feb 12-13 . . . . . . . . . . . 9.8 9O 68 78.1 Feb. 4 . . . . . . . . . . . . . . . Fe 3 . . . . . . . . . . . . . 9 9O 68 77.7 Feb. 5 . . . . . . . . . . . . . .. Feb 16 . . . . . . . . . . . .. 11 90 58 75.5 Feb. 6 . . . . . . . . . . . . . .. Feb 16 . . . . . . . . . . . .. 1O 88 58 75.0 Feb. 7 . . . . . . . . . . . . . .. Feb 7 . . . . . . . . . . . .. 10 88 58 73.8 Feb. 8 . . . . . . . . . . . . . .. Feb 17-18 . . . . . . . . . .. 9.7 88 58 74.0 Feb. . . . . . . . . . . . . . .. Fe . . . . . . . . . . . .. 9 88 58 73.6 Feb. 10 . . . . . . . . . . . . . .. Feb 19 . . . . . . . . . . . .. 9 88 58 73.6 Feb 11.. . Feb 20 . . . . . . . . . . . .. 9 84 58 73.8 Feb 12 . . . . . . . . . . . . . .. Feb 21 . . . . . . . . . . . .. 9 84 58 73.9 Feb 13 . . . . . . . . . . . . . .. Feb 22 9 84 58 74.5 Feb 14 . . . . . . . . . . . . . .. Feb 23 . . . . . . . . . . . .. 9 84 58 74.9 Feb 15 . . . . . . . . . . . . . .. Feb 24 . . . . . . . . . . . .. 9 84 58 75.7 Feb 16 . . . . . . . . . . . . . .. Feb 25 . . . . . . . . . . . .. 9 84 67 77.0 Feb 17 . . . . . . . . . . . . . .. Feb 26 . . . . . . . . . . . .. 9 84 7O 77.3 Feb 18 . . . . . . . . . . . . . .. Feb 27 . . . . . . . . . . . .. 9 84 68 76.7 Feb 19 . . . . . . . . . . . . . .. Feb 28 . . . . . . . . . . . .. 9 84 65 76.0 Feb 2O . . . . . . . . . . . . . . . Vlarch 1 . . . . . . . . . . . 10 82 61 73.8 Feb 24 . . . . . . . . . . . . . .. March 4 9 79 61 70.5 Feb 25 . . . . . . . . . . . . . . . March 5 . . . . . . . . . . . 9 79 61 70.0 Feb 26 . . . . . . . . . . . . . . . March 6 . . . . . . . . . . . 9 79 61 70.0 Feb 27 . . . . . . . . . . . . . .. March 8 10 79 55 67.0 Feb 28 . . . . . . . . . . . . . .. March 10 . . . . . . . . . . . 11 90 55 68.6 March . . . . . . . . . . . . . March 11 10 90 55 70.3 March 2 . . . . . . . . . . . . . . March 12 10 91 55 72.0 March 3 . . . . . . . . . . . . . March 13 10 92 55 73.3 March 4 . . . . . . . . . . . . . . March 14 10 92 55 74.5 March 5 . . . . . . . . . . . . . . March 15 10 92 55 75.7 March 6 . . . . . . . . . . . . . . March 16 1O 92 55 77.2 March 9 . . . . . . . . . . . .. March 17 8 92 77 83.0 March 10 . . . . . . . . . . . . . March 17 . . . . . . . . . . . 7 92 77 83.0 lVlarch 11 . . . . . ..'. . . . . .. March 18 . . . . . . . . . .. 7 92 77 83.1 March 12 . . . . . . . . . . . . . . March 19 . . . . . . . . . . . . 7 92 77 83.1 March15 . . . . . . . . . . . . ..March23............ 8 87 74 81.6 March16 . . . . . . . . . . . . ..March24............ 8 87 74 81.1 March17 . . . . . . . . . . . . ..March25............ 8 87 74 81.2 March18 . . . . . . . . . . . ..March26............ 8 87 74 81.0 March 19 . . . . . . . . . . . . .. March28............ 9 87 74 80.6 March20 . . . . . . . . . . . .. March29............ 9 87 74 80.4 March21 . . . . . . . . . . . . ..March29............ 8 87 74 80.3 March 22 . . . . . . . . . . . . . . March 30 . . . . . . . . . . . . 8 87 75 80.0 \/Iarch23 . . . . . . . . . . . . ..March31............ 8 87 75 79.1 March 24 . . . . . . . . . . . . . . April 1 . . . . . . . . . . . . . 8 87 75 79.4 March 25 . . . . . . . . . . . . . . April 1-3 . . . . . . . . . . . 8.5 87 73 78.8 March 26 . . . . . . . . . . . . . . April 4 . . . . . . . . . . 9 87 73 78.1 2:2 _ ' BULLETIN N0. 308. Table;2—Duration of Egg Stage-Continued _ Average Temperature Lot Laid Hatched period, N0. ~ days Max. I Min. Mean 1920 518 March 27 . . . . . . . . . . . . . . April 5 . . . . . . . . . . . . . 9 87 68 76.8 519 March 28 . . . . . . . . . . . . . April 6 . . . . . . . . . . . . . 9 87 68 76.1 520 March 29 . . . . . . . . . . . . . . April 8 . . . . . . . . . . . . . 10 87 68 76.3 521 March 30.... : . . . . . . . . . April 9 . . . . . . . . . . . . . 10 87 68 77.1 522 March 31 . . . . . . . . . . . . . . April 10 . . . . . . . . . . . . . 10 87 68 78.0 523 April 5 . . . . . . . . . . . . . . . April 15 . . . . . . . . . . . . . 10 85 71 79.4 524 April 8 . . . . . . . . . . . . . . . April 17 . . . . . . . . . . . . . 9 94 73 81.3 525 April 12 . . . . . . . . . . . . . . . April 20 . . . . . . . . . . . . . 8 94 73 83.0 The egg cavities were opened carefully at the conclusion of the average period of the egg stage at that season. This interfered least with natural conditions, and since a large number of observations were made it is believed that the average periods as given in Table 2 represent results in which the range of error has been reduced to a minimum. Temperatures were obtained by the use of a recording thermograph. For each period the single highest temperature and the single lowest temperature are given. The mean temperature is the average of the mean daily temperatures during the period. From April 23, 1918, to April 12, 1920, over 6,000 observations were made on the duration of the egg stage. The number of individual records were averaged and these data are given below. The greatest range in the daily periods was from 4.8 to 15 days.‘ The shortest period occurred on June 27, 1918, at a. mean temperature of 98.6 degrees F. and the longest period was in December, 1919, with a mean temperature of 77.7 degrees F. The average period of the dura- tion of the egg stage for the year 1919 was 8.7 days. The mean temperature for the year was 83.2 degrees F. The yearly variations in the duration of the egg stage are shown in Table 3. The influence of the mean temperature on the length of the egg stage is not always definite and the effect of temperatures ranging below the effective temperature is evident. Table 3 Yearly Variation in Duration of Egg Stage Period, Temperature, Date days mean May, 191s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 6.1 78.4 May, 1919 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 8.2 84.7 June, 1918 . . . . . . . . . . . . . . . ..Z . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 5.1 94.0 June, 1919 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 6.6 85.2 December, 1918 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12.3 81.6 December, 1919 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 11 .2 76.9 January, 1919 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . _ . . . .. 11 .2 79.1 January, 1920 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.3 79.1 In Table 4 is given a summary of the duration of the egg stage for each month during the period of these studies. It should be noted that all these observations were made in the laboratory, and the periods, especially during the cold season when heat was used, are doubtless considerably shorter than they would be under natural conditions. THE SWEET POTATO WEEVIL. 723 Table 4 Summary of Duration of Egg Stage Collections Nlonth Temperature, Longest Shortest Averag of eggs mean period period period observed 1918 April . . . . . . . . . . . . . . .. 72.3 12.4 9.8 11 8 May . . . . . . . . . . . . . . . .. 78.4 8 4.9 6.1 31 June . . . . . . . . . . . . . . . .. 94.0 6 4.8 5.1 3O December . . . . . . . . . . . . 81.6 14.1 1O 12.3 15 1919 January . . . . . . . . . . . . .. 79.1 14.3 9.2 11.2 31 February . . . . . . . . . . . . . 78.8 12 8.1 10.1 28 March . . . . . . . . . . . . . .. 80.4 12.5 9 11 31 April . . . . . . . . . . . . . . .. . 82.4 11.2 8 9.4 30 May . . . . . . . . . . . . . . . .. 84.7 11 7 8.2 31 June . . . . . . . . . . . . . . . . . 85.2 8 6 6.6 30 July . . . . . . . . . . . . . . . . . 92.3 7 5 5.6 31 August . . . . . . . . . . . . . .. 90.8 6.7 5 5.6 31 September . . . . . . . . . . . . 85.1 9 .5 7 8.1 28 October . . . . . . . . . . . . . . . 84.5 10 8 8.9 31 November . . . . . . . . . . . ._ 79.0 10 8 8.5 3O December . . . . . . . . . . . ., 76.9 15 9 11.2 27 1920 January.....' . . . . . . . .. 79.1 11 9 9.3 26 February... .' . . . . . . . .. 76.6 11 9 9.4 25 March . . . . . . . . . . . .. 77.0 10 7 8.5 23 Larva. Descripti0n.——The newly hatched larva is a delicate, white, legless grub, measuring less than 1 mm. in length. As the larva feeds and molts, the pure White color of the young individual soon becomes modi- fied by dark body contents, which show through the body wall. When full grown, the larva measures from 5 mm. to 8.5 mm. in length. It is sub-cylindrical in shape, and nearly uniform in diameter, except shortly before the posterior end, which tapers to a blunt point. The dorsum and sides are strongly wrinkled, and the entire body is covered with microscopic pubescence. The general color of this stage is soiled white or gray. The mandibles are dark-brown or black. The head is yel- lowish-brown, small, much narrower than the body, and oval in outline; it is longer than broad, and bears several long scattered hairs. The antennae are located at the lateral angle of the frons. The thoracic _ segments bear a number of long and rather conspicuous hairs. The legs are represented by enlarged tubercles, each bearing a number of setae. The abdominal segments are well defined, about equal in length, except the last two, which are smaller; each segment bears a few short dorsal and lateral hairs, which are visible only under the microscope. Views of the larva are shown in Figure 3. Duration of Larval Stage Observations were made in the laboratory" on the duration of the larval stage from May, 1918, to April, 1920. The beginning of this stage was determined accurately by carefully opening the egg cavity as is described in the paragraph on the duration of the egg stage. - At the conclusion of the average larval period it was again necessary to disturb the normal conditions by cutting open the larval burrow, in order to ascertain the exact time of pupation. The coverings were then care- fully replaced. In many cases as the larva 11ears maturity it feeds to- wards the surface of the tuber, leaving only the thin jacket covering the 24 BULLETIN N0. 308. pupal cell, and in such instances the necessary disturbance of natural conditions was reduced to a minimum. a In most cases the tubers contained several larvae, some of which were allowed to develop under normal conditions from egg deposition to pupation, and Were 11ot disturbed until the average time of the larval stage had been reached. The results obtained were in most cases ap- All of these periods were averaged and the proximately the same. data obtained are given in Table 5. Table 5 Duration of Larval Stage Average Temperature Lot Hatched Pupated period, N0. days Max Min. Mean 1918 1918 1 May 5-6 . . . . . . . . . . . . . May 20-22 . . . . . . . . . . . 15.7 92 68 79 .4 2 May . . . . . . . . . . . . . . . May 21-22 14.6 92 68 80.0 3 May 6-7 . . . . . . . . . . . . .. May21-23 15.4 92 68 80.0 4 May 7 . . . . . . . . . . . . . .. May 22-23 14.7 92 68 80.2 5 May 8 . . . . . . . . . . . . . .. May 21-23 14.2 92 68 80.1 6 May 9 . . . . . . . . . . . . . . . May 21-24 . . . . . . . . . .. 13.7 92 68 80.2 7 May 8-9 . . . . . . . . . . . . . . May 22-23 . . . . . . . . . . . 14 92 68 80.1 8 May 9 . . . . . . . . . . . . . .. May 23 . . . . . . . . . . . . . 14 92 68 80.1 9 May 9-10 . . . . . . . . . . . .. May 24 . . . . . . . . . . . . . 14. 92 68 80.2 10 May 9-11 . . . . . . . . . . . . . May 23-27 . . . . . . . . . . . 15.4 92 68 80.8 11 May 10 . . . . . . . . . . . . . .. ay 24 . . . . . . . . . . . .. 14 92 68 80.3 12 May 11 . . . . . . . . . . . . . .. May 25 . . . . . . . . . . . .. 14 89 68 80.2 13 May 11 . . . . . . . . . . . . . .. May 27 . . . . . . . . . . . .. 16 89 68 80.6 14 May 12 . . . . . . . . . . . . . . . May 27-28 . . . . . . . . . . . 15.7 87 68 80.5 15 May 13 . . . . . . . . . . . . . .. May 28-29 . . . . . . . . . . . 15.4 87 68 80.8 16 May 15 . . . . . . . . . . . . . .. ay29-31 14.8 89 68 81.7 17 May 16 . . . . . . . . . . . . . .. May30-31........... 14.7 89 74 82.2 18 May 17 . . . . . . . . . . . . . .. May 31-June 1 . . . . . .. 14.6 89 74 82.5 19 May 17-18 . . . . . . . . . . . .. May 31-June 1 . . . . . . . 14.7 89 74 82.5 20 May 18-19 . . . . . . . . . . . . . June -2 . . . . . . . . . . . . 14.2 89 74 82.7 21 May 18-20.............June 14.7 89 74 82.5 22 May 20 . . . . . . . . . . . . . . . June 14.9 89 74 82.6 23 May 21 . . . . . . . . . . . . . . . June 13.8 89 74 83.0 24 May 22 . . . . . . . . . . . . . .. June 13.6 89 74 83. 1 25 May 23 . . . . . . . . . . . . . . . June 13 89 74 83.2 26 May M . . . . . . . . . . . . . .. June 13.4 97 75 84.6 27 May 25 . . . . . . . . . . . . . .. June 13.4 97 75 85.4 28 May 26 . . . . . . . . . . . . . . . June 13.6 97 75 85.4 29 May 26-27 . . . . . . . . . . . . . June 13.8 97 75 86.0 30 May 27-28 . . . . . . . . . . . .. June 10 . . . . . . . . . . . . . 13.9 97 75 86.2 31 May 27-28 . . . . . . . . . . . . . June 10-12 . . . . . . . . . . . 14.1 100 75 87.5 32 May 29 . . . . . . . . . . . . . .. June 11-12 . . . . . . . . . .. 13.7 100 77 88.0 33 May 3O . . . . . . . . . . . . . .. June 13 . . . . . . . . . . . .. 14 102 77 88.8 34 May 31 . . . . . . . . . . . . . .. June 14 . . . . . . . . . . . .. 14 102 77 89.8 35 June 1 . . . . . . . . . . . . . .. June 15 . . . . . . . . . . . .. 14 102 77 90.7 36 June 3 . . . . . . . . . . . . . . . June 16 . . . . . . . . . . . .. 13 102 79 92.0 37 June 4 . . . . . . . . . . . . . .. June 18 . . . . . . . . . . . .. 14 102 81 93.1 38 June 5 . . . . . . . . . . . . . .. June 18 . . . . . . . . . . . .. 13 103 81 93.8 39 June 6 . . . . . . . . . . . . . .. June 19 . . . . . . . . . . . .. 13 107 87 94.8 40 June 6 . . . . . . . . . . . . . .. June 19 . . . . . . . . . . . .. 13 107 87 94.8 41 June 7 . . . . . . . . . . . . . . . June 19-20 12.5 107 87 95.2 42 June 8 . . . . . . . . . . . . . . . une 20 . . . . . . . . . . . . . 12 107 87 95.4 43 June 9 . . . . . . . . . . . . . . . June 22 . . . . . . . . . . . .. 13 107 87 95.9 44 June 10 . . . . . . . . . . . . . .. June 23 . . . . . . . . . . . .. 13 107 87 96.3 45 une . . . . . . . . . . . . . . . June 25-26 . . . . . . . . . . 13.5 107 89 97.2 46 June 12 . . . . . . . . . . . . . . . June 26 . . . . . . . . . . . . . 14 107 89 97.2 47 June 13 . . . . . . . . . . . . . .. une 28 . . . . . . . . . . . .. 15 107 89 97,4 48 June 14 . . . . . . . . . . . . . . . June 28-29 . . . . . . . . . . . 14.5 107 89 97.7 49 June 15 . . . . . . . . . . . . . .. June 30 . . . . . . . . . . . .. 15 107 89 97.8 50 June 16 . . . . . . . . . . . . . .. July . . . . . . . . . . . . .. 15 107 89 98.2 51 June 17 . . . . . . . . . . . . . .. July 2-3 . . . . . . . . . . .. - 15.5 107 89 98.1 52 June 18 . . . . . . . . . . . . . .. July 3-4 . . . . . . . . . . .. 15.6 107 85 98.0 53 une 1 . . . . . . . . . . . . . .. July 5 . . . . . . . . . . . .. 16 105 85 97.6 54 June 20 . . . . . . . . . . . . . .. July 6 . . . . . . . . . . . .. 16 103 85 97.3 55 June 21 . . . . . . . . . . . . . .. July 8 . . . . . . . . . . . . .. 17 103 .85 97.2 56 June 22 . . . . . . . . . . . . . .. July 10 . . . . . . . . . . . . .. 18 106 85 97.5 57 June 23 . . . . . . . . . . . . . .. July 11 . . . . . . . . . . . . .. 18 106 85 97.6 58 June 24 . . . . . . . . . . . . . .. July 12-13 . . . . . . . . . .. 18.8 106 85 97.7 59 June 26 . . . . . . . . . . . . . .. Jul 14 . . . . . . . . . . . . .. 18 106 84 97.2 60 June 26 . . . . . . . . . . . . . .. July 14-15 . . . . . . . . . . . 18.2 106 84 97.3 61 June 27 . . . . . . . . . . . . . .. y 15 . . . . . . . . . . . . .. 18 106 84 97.2 62 June 28 . . . . . . . . . . . . . .. July 16 . . . . . . . . . . . .. 18 106 84 97.1 63 June 29 . . . . . . . . . . . . . .. July 17 . . . . . . . . . . . .. 18 106 84 97.1 64 June 30 . . . . . . . . . . . . . . . July 16-18 . . . . . . . . . . . 17 106 84 97.0 65 July 1 . . . . . . . . . . . . . . .. July 17-18 . . . . . . . . . .. 16.7 106 84 96.9 THE SWEET POTATO WEEVIL. Table 5--Duration of Larval Stage—Continued Average Temperature Lot Hatched Pupated period, _ days Max. Mm. Mean 1918 66 July 1-2 . . . . . . . . . . . . .. July 15-19 . . . . . . . . . .. 16 106 84 97.0 67 July 3-4 . . . . . . . . . . . . .. July 17- . . . . . . . . . .. 16.3 106 84 97.3 68 July 4 . . . . . . . . . . . . . . .. July 2 . . . . . . . . . . . . .. 17 106 84 97.2 69 July 5 . . . . . . . . . . . . . . .. July . . . . . . . .. 17 106 84 97.5 7O Dec 26-28 . . . . . . . . . . . .. Jan 20-21 . . . . . . . . . .. 25 95 65 79.3 71 Dec. 8 . . . . . . . . . . . . . .. Jan 22-23 . . . . . . . . . .. 25.6 95 65 79.6 72 Dec. 29-30 . . . . . . . . . . . . . Jan 22-25 . . . . . . . . . . . 24.3 95 63 79.2 73 Dec. 30-Jan. 1, 1919. . .. Jan 25-26 . . . . . . . . . .. 24.8 95 63 79.0 74 Dec. 30-Ja]r1g1% 1919. . . . Jan 26-27 . . . . . . . . . . . 24.7 95 63 79.0 75 Jan. 2-3 . . . . . . . . . . . . .. Jan 26-27 . . . . . . . . . .. 24 93 63 78.8 76 Jan . . . . . . . . . . . . . . .. Jan 7 . . . . . . . . . . . . .. 24 93 63 78.8 77 Jan 6-7 . . . . . . . . . . . . .. Jan 27-28 . . . . . . . . . .. 22.3 93 63 79.3 78 Jan . . . . . . . . . . . . . . .. Jan 30-31 . . . . . . . . . .. 22.3 93 63 79.6 79 Jan 7-10 . . . . . . . . . . . .. Jan 8-31 . . . . . . . . . .. 21.3 93 63 79.6 80 Jan 9-11 . . . . . . . . . . . .. Jan 30-Feb 2 . . . . . .. 20.8 93 63 80.1 81 Jan 10-11 . . . . . . . . . . . .. Jan . . . . . . . . . . . . .. 20.4 93 63 80.2 82 Jan 11-12 . . . . . . . . . . . .. Jan 31-Feb. 3 . . . . . .. 20.9 - 93 63 80.0 83 Jan 12-15 . . . . . . . . . . . .. Feb. 1 . . . . . . . . . . . .. 19.1 93 63 80.1 84 Jan 14-16 . . . . . . . . . . . .. Feb. 3-9 . . . . . . . . . . .. 21.6 93 63 79.3 85 Jan. 4-1 . . . . . . . . . . . .. Feb. 4-11 . . . . . . . . . .. 23 93 63 75.5 86 Jan. 15-17 . . . . . . . . . . . . . Feb. 5-13 . . . . . . . . . . . 23 93 63 76.6 87 Ian. 16-18 . . . . . . . . . . . . . Feb. 6-11 . . . . . . . . . .. 21.5 93 63 79.8 88 Ian. 17-18 . . . . . . . . . . . .. Feb. 7-10 . . . . . . . . . .. 21.3 93 63 79.5 89 Jan. 18-19 . . . . . . . . . . . . . Feb. 8-10 . . . . . . . . . . . 20.9 93 63 79.2 90 Ian. 19-20 . . . . . . . . . . . .. Feb. 9-12 . . . . . . . . . . . 20.6 93 63 79.0 91 Ian. 19-20 . . . . . . . . . . . . . Feb. 8-11 . . . . . . . . . . . 20.5 93 63 79.2 92 Jan. 19-22 . . . . . . . . . . . . . Feb. 8-10 . . . . . . . . . . . 20.1 93 63 79.6 93 Jan. 20-21 . . . . . . . . . . . . . Feb. 8-11 . . . . . . . . . . . 20.4 93 63 79.3 94 Jan. 20 . . . . . . . . . . . . . . .. Feb. 10-17 . . . . . . . . . .. 22.4 93 63 80.0 95 Jan 21-22 . . . . . . . . . . . .. Feb. 11-14 . . . . . . . . . .. 21.8 93 63 79.7 96 Jan . . . . . . . . . . . . . . . . Feb. 13-19 . . . . . . . . . . . 24.3 93 63 79.6 97 Jan 23-24 . . . . . . . . . . . . . Feb. 14-27 . . . . . . . . . .. 24.7 93 63 79.4 98 Jan 24-25 . . . . . . . . . . . .. Feb 15-19 . . . . . . . . . .. 23.5 93 63 79.6 99 Jan 25-28 . . . . . . . . . . . .. Feb 15-18 . . . . . . . . . .. 22.5 93 65 79.7 100 Jan 26-28 . . . . . . . . . . . .. Feb 18-25 . . . . . . . . . . . 23.1 93 63 79.4 101 Jan 27-29 . . . . . . . . . . . .. Feb 17-19 . . . . . . . . . .. 21.3 93 65 79.9 102 Jan 28 . . . . . . . . . . . . . . .. Feb 17-20 . . . . . . . . . .. 21.1 93 65 80.1 103 Jan 28-29 . . . . . . . . . . . .. Feb 8-23 . . . . . . . . . .. 22.5 93 63 79.7 104 Jan 29-30 . . . . . . . . . . . .. Feb 20-24 . . . . . . . . . .. 22.2 93 63 79.5 105 Jan 30-Feb 1 . . . . . . . .. Feb 1-28 . . . . . . . . . .. 24.8 93 63 79.7 106 Jan 31-Feb 1 . . . . . . . .. Feb. 24-March 5. . . . . 25.6 101 63 80.6 107 Jan 31-Feb 6 . . . . . . . . . . Feb. 25-March 2.. . . . . 24.8 93 63 79 6 108 Feb. -5 . . . . . . . . . . . . . . Feb. 26-Mareh 3 . . . . . . 25.3 95 63 79.8 109 Feb. 5-6 . . . . . . . . . . . . . . Feb. 28-March 3. . . . . 24.6 95 63 80.3 110 Feb. 7 . . . . . . . . . . . . . .. March 1-4 . . . . . . . . .. 23.9 101 63 80.8 111 Feb. 7-8 . . . . . . . . . . . . .. March 2-6 . . . . . . . . .. 23.2 101 63 81.3 112 Feb. 8-9 . . . . . . . . . . . . .. March 1-8 . . . . . . . . .. 22.5 101 63 81.4 113 Feb. 9-13 . . . . . . . . . . . .. March 1-8 . . . . . . . . . . 22.1 101 63 81.4 114 Feb 11-12 . . . . . . . . . . . .. March 3-7 . . . . . . . . .. 20.4 101 63 81.9 115 March 3-11 . . . . . . . .. 19.9 101 63 82.7 116 . March 7-9 . . . . . . . . .. 22.4 101 63 79.7 117 March 3-5 . . . . . . . . .. 20.9 101 63 81.8 118 March 3-11 . . . . . . . .. 20.4 101 63 81.4 119 March 6-15 . . . . . . . .. 22.7 101 63 81.0 120 March 5-15 . . . . . . . . . 22.3 101 63 81.0 121 March 7-16; . . . . . . .. 22.2 101 63 81.0 122 March 9-12 . . . . . . . .. 20.7 101 63 81.0 123 Ma ch 9-12 . . . . . . . .. 21.3 101 63 81.0 124 March 10-12 . . . . . . . . . 22.2 101 63 81.0 125 March 1 -16 . . . . . . . .. 23.1 101 63 81.0 126 March 12-17 . . . . . . . . . 22.6 101 63 81.1 127 March. 1 -21 . . . . . . . . 23.1 101 63 80.2 128 March 14-23 . . . . . . . . . 22.6 101 71 80.8 129 Marc-h 16-22 . . . . . . . . . 22.5 101 71 80.9 130 March 18-24 . . . . . . . .. 23.9 101 71 81.0 131 March 21-25 . . . . . . . . . 23.8 101 71 80.9 132' Feb. 26-27 . . . . . . . . . . . .. March 22-25 . . . . . . . . . 23.8 101 . 71 81.2 133 Feb. 27-March 1 . . . . . . . March 22-26 . . . . . . . . . 23.5 101 71 80.6‘ 134 March 1-2 . . . . . . . . . . . . . March 24-28. ._ . . . . . . . 23.8 101 71 80.4 135 March 4-8 . . . . . . . . . . . . March 28-Apr1l 6.. . . . 24.5 98 71 79.4 136 March 4 . . . . . . . . . . . . .. March 29-April 1. . . . . 25.2 98 71. 79.6 137 March 4-6 . . . . . . . . . . . . March 30-April 4.. . . . 26.1 98 71 79.4 138 March 6-7 . . . . . . . . . . .. March 31-April 4.. . .. 25.6 90 71 79.3 139 March 7-8 . . . . . . . . . . . . April 1-6 . . . . . . . . . . . 25.7 88 71 78.8 *140 March 7-8 . . . . . . . . . . . . . . . ._ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 141 March 8-9 . . . . . . . . . . .. Aprll 2-9 . . . . . . . . . .. 26.7 88 71 79.2 *Inc0m; lete record. 26 BULLETIN N0. 308. Table 5——-Duration of Larval Stage-—Continued Average Temperature Lot Hatched Pupated period, days Max Min Mean 1919 1919 142 March 9 . . . . . . . . . . . April 3-11 . . . . . . . . . . 25.8 88 71 79.2 143 March 10 . . . . . . . . . . . . .. April 5-11 . . . . . . . . .. 26.9 88 71 79.4 144 March 11-14 . . . . . . . . . . . April 7-9 . . . . . . . . . . . 27.7 88 71 79.3 145 March 12 . . . . . . . . . . . . . . April 7-12 . . . . . . . . . . 27.8 90 71 79.4 146 March 12-13 . . . . . . . . . April 9-18 . . . . . . . . . . 28 95 71 80.1 147 March 14-16 . . . . . . . . . .. April 8-13 . . . . . . . . . . 27.8 95 71 79.6 148 March 15-16 . . . . . . . . . . . April -19 . . . . . . . . . . 28.2 95 71 80.2 149 March 16-17 . . . . . . . . . . . April 10-16 . . . . . . . . . . 28 95 71 80.1 .150 March 17-19 . . . . . . . . . . . April 14-20 . . . . . . . . . . 28.2 95 71 80.3 .151 March 18-19 . . . . . . . . . . . April 13-17 . . . . . . . . . . 27.5 95 71 80.2 152 March19-20 . . . . . . . . . . . April 15-19 . . . . . . . . . . 26.8 95 71 80.4 153 March 20-22 . . . . . . . . . . . April 17-18 . . . . . . . . . . 27.1 95 71 80.5 .154 March 22-23 . . . . . . . . . . . April 17-24 . . . . . . . . . . 27.5 95 71 81.2 155 March 22-24 . . . . . . . . . . . April 19-21 . . . . . . . . . . 27.1 95 71 80.9 .156 March 24-25 . . . . . . . . . . . April 19-20 . . . . . . . . . . 26.5 95 71 80.9 157 March 25 . . . . . . . . . . . . . . April 19-21 . . . . . . . . . . 26 95 71 81.1 158 March 25-26 . . . . . . . . . . . April 21-25 . . . . . . . . . . 26.7 95 71 81.5 159 March 26-27 . . . . . . . . . . . April 22-26 . . . . . . . . . . 27.4 95 71 81.7 160 March 28 . . . . . . . . . . . . . . April 23-25 . . . . . . . . . . 26.7 95 71 82.0 161 March 29-30 . . . . . . . . . . . April 25-27 . . . . . . . . . . 26.5 95 71 82.1 162 March 3l-April 1.. . . ; .. April 25-28 . . . . . . . . . . 25.7 95 71 82.5 163 March 30-April 1 . . . . . . . April 26-28 . . . . . . . . . . 25.9 95 71 82.4 164 April 2 . . . . . . . . . . . . ; . . April 27-28 . . . . . . . . . . 25.2 95 71 82.8 165 April 3 . . . . . . . . . . . . . . . April 26-30 . . . . . . . . . . 25.2 95 71 83.2 166 April 3-4 . . . . . . . . . . . . . April 28-29 . . . . . . . . . . 25. 1 95 71 83.2 167 April 4-5 . . . . . . . . . . . . . April 29-30 . . . . . . . . . . 25.1 95 71 83.3 168 April 5-6 . . . . . . . . . . . . . April 30-May 1 . . . . . . 24.8 95 71 83.5 i169 April 6 . . . . . . . . . . . . . . . April 27-30 . . . . . . . . . . 22.7 95 71 83.7 170 April 7 . . . . . . . . . . . . . . . pril 29-30 . . . . . . . . . . 22.7 95 71 83.3 171 April 8 . . . . . . . . . . . . . .. May 1-2 . . . . . . . . . . .. 23.3 95 71 83.7 172 April 9 . . . . . . . . . . . . . .. May 1-3.. 22.5 95 71 83.9 173 April 10 . . . . . . . . . . . . . . . May 2-3. . 22.5 95 70 84.1 174 April 10-11 . . . . . . . . . . . . May 2-4. . 22.3 95 70 84.2 175 April 11-12 . . . . . . . . .;.. May 3-4. . 21.7 95 7O 84.4 176 April 12-13 . . . . . . . . . . . . May 3-5 . . . . . . . . . . . 21.2 95 72 84.7 177 April 13 . . . . . . . . . . . . . .. May 4-5 . . . . . . . . . . .. 21.1 95 72 84.7 178 April 14 . . . . . . . . . . . . . . . May 4-5 . . . . . . . . . . . . 20.3 95 72 84.6 179 April 15 . . . . . . . . . . . . . . . May 5-7. . 21 93 72 84.4 180 April 16. . . ." . . . . . . . . . .. May 5-6 . . . . . . . . . . . 20.3 93 72 84.6 181 April 17 . . . . . . . . . . . . . .. May 5-7.. 19 93 - 75 84.7 182 pril 18 . . . . . . . . . . . . . .. May 7-10 . . . . . . . . .. 21.1 93 75 83.8 183 April 19-20 . . . . . . . . . . . . May 9-10 . . . . . . . . . . 20.5 93 75 83.4 184 April 20-21 . . . . . . . . . . . . . May 10-15 . . . . . . . . . . 20 93 71 83.3 185 pr1l22 . . . . . . . . . . . . . .. May 11-14 . . . . . . . . . .. 20 93 71 83.3 186 April 23 . . . . . . . . . . . . . . . May 12-14 . . . . . . . . . . . 19.7 93 71 83.3 187 April 23-24 . . . . . . . . . . . . May 12-15 . . . . . . . . . . . 2O 93 71 83.6 188 April 24-25 . . . . . . . . . . . . May 14-17 . . . . . . . . . . 21 100 71 84.3 189 April 25-26 . . . . . . . . . . . . May 15-17 19.8 100 71 84.3 190 April 25-26 . . . . . . . . . . .. May 16-17 . . . . . . . . . . . 20.4 100 71 84.3 ‘191 April 26-27 . . . . . . . . . . .. May 16-17 . . . . . . . . . .. 19.8 100 71 84.3 192 April 27-28 . . . . . . . . . . .. May 16-17 . . . . . . . . .. 19.3 100 71 84.4 193 April 28 . . . . . . . . . . . . . . . May 17-21 20.1 100 71 84.5 194 April 28-29 . . . . . . . . . . . . May 19-20 . . . . . . . . . . 20.1 100 71 84.5 195 April 29 . . . . . . . . . . . . . .. May 20-21 . . . . . . . . . . . 20.1 100 ' 71 84.4 196 April 30-May 1... . . . . .. May 19-21 . . . . . . . . . . 19.7 100 71 84.5 197 May 1 . . . . . . . . . . . . . .. May 21-24 . . . . . . . . . .. 20.7 100 71 84.7 1198 May 2 . . . . . . . . . . . . . .. May 22-23 . . . . . . . . . .. 20.1 100 71 84.6 199 May 3-4 . . . . . . . . . . . . .. May 22-24 . . . . . . . . . .. 19.9 100 71 84.5 200 May 4 . . . . . . . . . . . . . .. May 23-25 19.9 100 71 84.5 201 May 5 . . . . . . . . . . . . . . . Vlay 24-25 19.5 100 71 84.3 202 May 6 . . . . . . . . . . . . . . . May 24-25 19.1 100 71 84.3 203 May 7 . . . . . . . . . . . . . .. May 25-26 . . . . . . . . . . . 18.2 100 71 84.5 204 May 8 . . . . . . . . . . . . . .. May 26-27 . . . . . . . . .. 18.7 100 71 84.7 205 ay 9 . . . . . . . . . . . . . . . May 27 . . . . . . . . . . . .. 17.9 100 71 85.1 206 May 10 . . . . . . . . . . . . . . . May 27-28 18.3 100 71 85.7 207 May 11-12 . . . . . . . . . . . . . May 28 . . . . . . . . . . . . . 17.2 100 75 86.3 208 May 12-13 . . . . . . . . . . . . . May 28-29 16.1 100 75 86.8 209 May 14 . . . . . . . . . . . . . . . May 29-31 16.7 100 76 86.5 210 May 15-16 . . . . . . . . . . . .. June 1 . . . . . . . . . . . .. 16.1 100 76 86.1 211 May 1 . . . . . . . . . . . . . .. June 3-5 . . . . . . . . . .. 16.3 94 76 84.7 212 May 18 . . . . . . . . . . . . . .. June 3-4. . 16.1 94 76 85.0 213 May 18 . . . . . . . . . . . . . . . June 4-5.. 17.5 94 76 84.7 214 May 19 . . . . . . . . . . . . . .. June . . . . . . . . . . . .. 17.1 94 76 84.5 215 May 19-20 . . . . . . . . . . . .. June 4-5. 17 94 76 84.5 216 May 20-21 . . . . . . . . . . . . . June 5-6 . . . . . . . . . . . . 17 94 76 84.4 217 May 21 . . . . . . . . . . . . . .. June 7 . . . . . . . . . . . .. 17 94 76 84.5 218 May 22 . . . . . . . . . . . . . .. June 8 . . . . . . . . . . . .. 17.1 100 76 84.9 219 May 23 . . . . . . . . . . . . . .. June 9 . . . . . . . . . . . .. 17 101 76 85.5 220 ay 24 . . . . . . . . . . . . . .._June 9-10 . . . . . . . . .. 16.2 101 76 85.5 *1 ncomplete record. THE SWEET POTATO WEEVIL. 27 Table 5——Dura.tionjof Larval Stage-Continued Average Temperature Lot Hatched Pupated period, days Max Min. Mean 1919 1919 221 May 25 . . . . . . . . . . . . . .. June 10-11 . . . . . . . . .. 16.1 101 76 85.3 222 May 26 . . . . . . . . . . . . . . . June 10-11 . . . . . . . . . .. 16 101 76 85 .5 223 May 26-27 . . . . . . . . . . . . . June 11 . . . . 15.7 101 76 85.5 224 . ay 28 . . . . . . . . . . . . . . . June 11-12.. 14.5 101 76 85.8 225 May 29 . . . . . . . . . . . . . . . June 12 . . . . . . . . . . . . . 14 101 76 85 .8 226 May 30-31 . . . . . . . . . . . . . June 14-15 . . . . . . . . . . . 14.8 101 76 86.5 227 May 31 . . . . . . . . . . . . . . . June 15 . . . . . . . . . . . .. 15 101 76 86.7 228 June . . . . . . . . . . . . . . . June 16-17 . . . . . . . . . . . 15.4 101 76 86.6 229 June 1-2 . . . . . . . . . . . . .. June 16-17 . . . . . . . . . .. 15.8 101 76 86.6 230 June 2 . . . . . . . . . . . . . . . June 17-18 . . . . . . . . . .. 15.5 101 76 86.6 231 June 3 . . . . . . . . . . . . . . . June 18-22. . .. . . . . . .. 16.3 101 76 87.3 232 June 4 . . . . . . . . . . . . . . . June 19-21 . . . . . . . . . . . 15.6 101 76 87.8 233 June 5 . . . . . . . . . . . . . . . June 20-22 . . . . . . .'. . . . 16 101 76 88. 1 234 June 7 . . . . . . . . . . . . . . . June 21-22 . . . . . . . . . .. 14.4 101 76 88.7 235 June 8 . . . . . . . . . . . . . .. June 22-23........... 14.1 101 76 88.3 236 June 9 . . . . . . . . . . . . . . . June 21-24 . . . . . . . . . . . 14.2 96 76 87.8 237 June 1O . . . . . . . . . . . . . .. June 24 . . . . . . . . . . . .. 14.1 96 76 87.2 238 June 10 . . . . . . . . . . . . . . . June 25-26 . . . . . . . . . . . 15. 1 96 76 87.4 239 June 11 . . . . . . . . . . . . . . . June 26-27 . . . . . . . . . . 15. 1 96 80 87 .7 240 June 11 . . . . . . . . . . . . . . . June 27 . . . . . . . . . . . . . 16 96 8O 87.7 241 June 12 . . . . . . . . . . . . . .. June 28-29 . . . . . . . . .. 16.3 95 80 87 .7 242 June 13-14 . . . . . . . . . . . . . June 29-30 . . . . . . . . . . . 16 95 8O 87.8 243 June 14 . . . . . . . . . . . . . . . June 29-30 . . . . . . . . . . . 15.7 94 80 87.7 244 June 15 . _ . . . . . . . . . . . .. June 29 . . . . . . . . . . . .. 14 94 80 88.2 245 June 15-17 . . . . . . . . . . . . . June 30-July 1 . . . . . . . 13.6 96 81 88.7 246 June 17-18 . . . . . . . . . . . . . July 1 . . . . . . . . . . . . . . 13.7 96 81 89.2 247 June 19 . . . . . . . . . . . . . . . July 2 . . . . . . . . . . . . . . 13 96 81 89.5 248 June 20 . . . . . . . . . . . . . .. July 3 . . . . . . . . . . . . .. 13 96 81 89.9 249 June 21 . . . . . . . . . . . . . .. July 6-7 . . . . . . . . . . .. 13.9 97 81 90.8 250 June 22-23 . . . . . . . . . . . . . July 7 . . . . . . . . . . . . . . 14.8 97 83 91 .0 251 June 22 . . . . . . ..' . . . . . .. July 7-8 . . . . . . . . . . .. 15.6 97 84 91 .0 252 June 23-24 . . . . . . . . . . . . . July . . . . . . . . . . . . . . 15.6 97 84 91.5 253 June 25 . . . . . . . . . . . . . . . July . . . . . . . . . . . . . . 14 97 84 91.9 254 June 26 . . . . . . . . . . . . . . . July 9-10 . . . . . . . . . . . 13.8 97 84 92.2 255 June 27-28 . . . . . . . . . . . . . JulyflO . . . . . . . . . . . . . . 12 .7 98 84 ‘92.6 256 June 28-29 . . . . . . . . . . . . . uly 10-11 . . . . . . . . . . . 12.2 100 85 93.1 257 June 28-29 . . . . . . . . . . . . . l 11 . . . . . . . . . . . . . . 12.4 100 85 93.1 258 June 29-30 . . . . . . . . . . . . . July 11-12 . . . . . . . . . . . 11 .7 100 85 93.7 259 June 30 . . . . . . . . . . . . . . . July 12-13 . . . . . . . . . . . 12.2 100 85 94.2 260 July 1 . . . . . . . . . . . . . . .. July 13-14 . . . . . . . . . .. 12.8 100 85 94.6 261 July 2 . . . . . . . . . . . . . . . . July 14-16 . . . . . . . . . . . 13 100 85 94.7 262 July 3 . . . . . . . . . . . . . . . . July 16 . . . . . . . . . . . . .. 13 100 85 94.7 263 July 4 . . . . . . . . . . . . . . .. July 17 . . . . . . . . . . . . .. 13 101 85 94.8 264 July 5 . . . . . . . . . . . . . . .. July 18-19 . . . . . . . . . .. 13.2 101 85 94.4 265 July 6-7 . . . . . . . . . . . . .. July 19 . . . . . . . . . . . . .. 12.3 101 85 94.5 266 July 7-8 . . . . . . . . . . . . .. July 19 . . . . . . . . . . . . .. 11.2 101 85 94.7 267 July 8-10 . . . . . . . . . . . . . July 19-20 . . . . . . . . . . . 10.3 101 87 95.1 268 July 8-11 . . . . . . . . . . . .. July 21 . . . . . . . . . . . . . . 12.2 101 87 95.0 269 July 10 . . . . . . . . . . . . . . . . July 22 . . . . . . . . . . . . . . 12 101 87 95.0 270 July 11 . . . . . . . . . . . . . . .. July 22-23 . . . . . . . . . . . 11.7 101 87 94.7 271 luly 12 . . . . . . . . . . . . . . . . July 23-24 . . . . . . . . . . . 12.2 101 86 93.7 272 July 13 . . . . . . . . . . . . . . . July 24-25 . . . . . . . . . . . 12.7 101 86 93.2 273 July 14 . . . . . . . . . . . . . . . . July 27-28 . . . . . . . . . . . 13.1 101 86 92.6 274 July 15-16 . . . . . . . . . . . . . July 28-29 . . . . . . . . . . . 12.8 101 86 92.7 275 July 16-17. .- . . . . . . . . . .. July 3O . . . . . . . . . . .. 13.7 101 86 92.6 276 July 17-20 . . . . . . . . . . . . . July 30-Aug. 3 . . . . . . . 14.6 98 86 92.7 277 July 18-19 . . . . . . . . . . . . . Aug. 1 . . . . . . . . . . . . . 14.3 98 86 92.6 12 98 86 92.5 13.5 98 86 92.7 13 .3 98 86 92.8 14 98 86 93 . 0 13 .5 98 87 93 .4 13 .5 98 85 93 . 5 13.2 98 85 93.6 13 .4 98 85 93.7 13 .2 98 90 93 .9 12 98 9O 94.0 13 98 88 93 .6 12 .8 98 88 93 .4 12 .5 98 88 93 . 1 11 .3 98 88 93 .0 11 .3 98 88 93 .0 11 .4 98 88 92.8 11 .6 98 88 92 .6 12 98 88 92.5 12 98 85 92.2 28 BULLETIN N0. 308. Table 5—-Duration of Larval Stage-Continued Average Temperature Lot Hatched Pupated penod, days Max. Min. Mean 1919 1919 299 Aug. 8 . . . . . . . . . . . . . . . Aug. 19-20 . . . . . . . . . . . 11.5 98 85 92.0 300 Aug. 9 . . . . . . . . . . . . . . . Aug. 20-21 . . . . . . . . . . . 11.8 97 85 91 .4 301 Aug. 10 . . . . . . . . . . . . . .. Aug. 21 . . . . . . . . . . . .. 11 95 85 91 .2 302 Aug. 11 . . . . . . . . . . . . . . . Aug. 22 . . . . . . . . . . . . . 11 95 84 90.6 303 Aug. 12 . . . . . . . . . . . . . . . Aug. 23 . . . . . . . . . . . .. 11 95 81 90.0 304 Aug. 13 . . . . . . . . . . . . . .. Aug 25 . . . . . . . . . . . .. 12 95 81 89.2 305 Aug. 14 . . . . . . . . . . . . . .. Aug 26 . . . . . . . . . . . .. 12 95 80 88.7 306 Aug. 15 . . . . . . . . . . . . . . . Aug 26-27 . . . . . . . . . .. 11.8 95 80 88.2 307 Aug. 16 . . . . . . . . . . . . . . . Aug 27-28 11.2 95 80 87.8 308 Aug. 18 . . . . . . . . . . . . . .. Au 28-29 11.6 95 8O 87.2 309 Aug. 19 . . . . . . . . . . . . . . . Aug 29-30 11.3 94 80 87.4 310 Aug. 20 . . . . . . . . . . . . . .. Aug 1 . . . . . . . . . . . . . 11 94 80 87.4 311 Aug. 21 . . . . . . . . . . . . . .. Sept. 2-3 . . . . . . . . . .. 11.5 95 77 87.0 312 Aug. 22 . . . . . . . . . . . . . . . Sept. 2 . . . . . . . . . . . . . 11 95 78 87.5 313 Aug. 22-23 . . . . . . . . . . . . . Sept. 2-3 . . . . . . . . . . . ll .5 95 77 87. 0 314 Aug. 23-24 . . . . . . . . . . . . . Sept. . . . . . . . . . . . . . 11 95 77 87.4 315 Aug. 25. . . . . . . . . . . . . .. Sept. 4-6 . . . . . . . . . .. 11.6 95 77 86.7 316 Aug. 26 . . . . . . . . . . . . . . . Sept. 5 . . . . . . . . . . . . . 10 95 77 87.0 317 Aug. 27 . . . . . . . . . . . . . . . Sept. 6 . . . . . . . . . . . . . 10 95 77 86.8 318 Aug. 28 . . . . . . . . . . . . . . . Sept. 8-9 . . . . . . . . . . . 12.2 95 77 86.3 319 Aug. 29 . . . . . . . . . . . . . .. Sept 11-12 . . . . . . . . .. 13.3 96 77 87.0 320 Aug. 29-30 Sept 13-15 . . . . . . . . . . 15.7 97 77 86.8 321 Aug. 3O . . . . . . . . . . . . . . . Sept . . . . . . . . . . . . . 17 97 77 86.4 322 Sept. 1 . . . . . . . . . . . . . . . Sept. 16-18 . . . . . . . . . . 15.6 97 77 85.8 323 Sept. 2 . . . . . . . . . . . . . .. Sept. 17 . . . . . . . . . . . . . 15 97 77 86.0 324 Sept. 3 . . . . . . . . . . . . . . . Sept. 18 . . . . . . . . . . . . . 15 97 77 86.2 325 Sept. 4 . . . . . . . . . . . . . . . Sept. 19 . . . . . . . . . . . . . 15 97 77 86.5 326 Sept. 5 . . . . . . . . . . . . . .. Sept. 0 . . . . . . . . . . . .. 15 97 77 86.8 327 Sept. 6-7 . . . . . . . . . . . . . Sept. 20-21 . . . . . . . . . . 14.7 97 77 87.1 328 Sept. 8 . . . . . . . . . . . . . . . Sept. 21-22 . . . . . . . . . . 13.2 97 77 87.5 329 Sept. 9 . . . . . . . . . . . . . . . Sept. 22 . . . . . . . . . . . . . 13 97 77 87.5 330 Sept. 11 . . . . . . . . . . . . . . . Sept. 22-23 . . . . . . . . . . 11 . 97 77 86.5 331 Sept. 12 . . . . . . . . . . . . . . . Sept. 23 . . . . . . . . . . . . . 11 97 77 86.0 332 Sept. 13 . . . . . . . . . . . . . . . Sept. 4 . . . . . . . . . . . .. 11 92 75 84.8 333 Sept. 14-16 . . . . . . . . . . . . Sept. 24-28 . . . . . . . . . . 12.3 91 74 83.5 334 Sept. 16 . . . . . . . . . . . . . . . Sept. 26-27 . . . . . . . . . . 11 .2 91 74 83.0 335 Sept. 17 . . . . . . . . . . . . . . . Sept. 28-29 . . . . . . . . . . 11.7 91 74 83.5 336 Sept. 18 . . . . . . . . . . . . . . . Sept. 30 . . . . . . . . . . . . . 12 96 74 83.7 337 Sept. 19 . . . . . . . . . . . . . .. Oct. 3 . . . . . . . . . . . . 14.5 96 74 84.3 338 Sept. 20-22 . . . . . . . . . . . . Sept. 30-Oct 6 . . . . . . . 14.1 96 74 84.4 339 ept 21-22 . . . . . . . . . . .. Oct. -10 . . . . . . . . . .. 16.5 96 74 84.4 340 Sept . . . . . . . . . . . . . . . Oct 8-10 . . . . . . . . . . . 16.8 96 74 84.4 *341 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . , _ _ _ _ _ _ _ _ _ _ _ , _ , _ _ , _ _ . . . . , _ , _ *342 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 343 Sept 23 . . . . . . . . . . . . . .. Oct 8 . . . . . . . . . . . . .. 15 96 74 84.2 344 Sept. 24 . . . . . . . . . . . . . . . Oct 10-14 . . . . . . . . . . . 16.8 96 74 83.6 345 Sept 25-26 . . . . . . . . . . .. Oct 8-15 . . . . . . . . . .. 16.7 96 74 83.4 346 Sept. 27 . . . . . . . . . . . . . . . Oct 15-16 . . . . . . . . . . . 18.2 96 74 83.7 347 Sept. 28 . . . . . . . . . . . . . . . Oct 17 . . . . . . . . . . . . . . 19 96 73 83.4 348 Sept. 29‘. . . . . . . . . . . . . . . Oct 18 . . . . . . . . . . . . . . 19 96 69 82.5 349 Sept. 30 . . . . . . . . . . . . . . . Oct 17-20 . . . . . . . . . . . 19.2 94 69 81.3 350 Oct. 1-2 . . . . . . . . . . . . . . Oct. 22-23 . . . . . . . . . . . 21 94 69 81.0 351 Oct. 2 . . . . . . . . . . . . . . .. Oct 21-24 . . . . . . . . . .. 20.2 94 69 81.0 352 Oct. 3 . . . . . . . . . . . . . . .. Oct 23-25 . . . . . . . . . .. 20.5 93 69 81.1 353 Oct. 4 . . . . . . . . . . . . . . .. Oct 24-25 . . . . . . . . . .. 20.2 93 69 80.8 354 Oct. 5 . . . . . . . . . . . . . . .. Oct 5 . . . . . . . . . . . . .. 20 93 69 80.5 355 Oct. 6 . . . . . . . . . . . . . . .. Oct . . . . . . . . . . . . .. 20.2 91 69 80.5 356 Oct. 7 . . . . . . . . . . . . . . .. Oct 26-28 . . . . . . . . . .. 20 91 69 80.9 357 Oct. 7-8 . . . . . . . . . . . . .. Oc 27-30 . . . . . . . . . .. 20.4 91 69 80.2 358 Oct. 9-10 . . . . . . . . . . . . . Oct. 29-31 . . . . . . . . . . . 20 91 69 81.3 359 Oct. 1 . . . . . . . . . . . . . . . . Oct. 30-31 . . . . . . . . . . . 20.8 90 69 80.0 360 Oct 11 . . . . . . . . . . . . . . . . Oct. 31-Nov 3 . . . . . . . 21.5 90 69 79.2 361 Oct. 12 . . . . . . . . . . . . . . .. Oct 31-Nov 1 . . . . . .. 21.3 90 69 79.7 362 Oct. 3 . . . . . . . . . . . . . . .. Nov 1-3 . . . . . . . . . .. 21.1 90 69 79.5 363 Oct. 14-15 . . . . . . . . . . . . . Nov 5-8 . . . . . . . . . . . 23.6 90 69 79.4 364 Oct. 15-16 . . . . . . . . . . . .. Nov 7-8 . . . . . . . . . .. 23.5 90 69 79 .6 365 Oct 17-18 . . . . . . . . . . . .. Nov 9-10 . . . . . . . . .. 23.7 94 69 80.2 366 Oct 18»1 . . . . . . . . . . . .. Nov 10-11 . . . . . . . . .. 22.6 94 7O 80.6 367 Oct 2O . . . . . . . . . . . . . . .. Nov 11 . . . . . . . . . . . .. 22 94 72 81.4 368 Oct. 21 . . . . . . . . . . . . . . . . Nov 12 . . . . . . . . . . . . . 22 94 72 81 .3 369 Oct. 22 . . . . . . . . . . . . . . . . Nov 13-14 . . . . . . . . . . 22.3 94 66 80.9 370 Oct 23 . . . . . . . . . . . . . . .. Nov 13-15 . . . . . . . . .. 22.2 94 66 80.6 371 Oct . . . . . . . . . . . . . . . . Nov 14-15 . . . . . . . . . . 22.4 94 66 80.4 372 Oct 24-25 . . . . . . . . . . . .. Nov 16 . . . . . . . . . . . .. 22.8 94 66 80.2 373 Oct 25-26 . . . . . . . . . . . .. Nov 17 . . . . . . . . . . . .. 22.5 94 66 79.8 374 Oct. 27 . . . . . . . . . . . . . . . . Nov 18 . . . . . . . . . . . . . 22 A 94 ‘ 66 79.1 375 Oct. 28 . . . . . . . . . . . . . . . . Nov 18 . . . . . . . . . . . . . 21 94 66 79.0 *Inc0mplete record. THE SWEET POTATO WEEVIL. 29 Table 5—-Duration of Larval Stage-Continued Average Temperature Lot Hatched Pupated period, days Max. Min. Mean 1919 1919 376 Oct. 28-29 . . . . . . . . . . . . . Nov. 18-19 . . . . . . . . . . 22.3 94 66 79 O 377 Oct. 29-30 . . . . . . . . . . . . . Nov. 1 . . . . . . . . . . . . . 20.9 94 66 79 0 378 Oct. 30 . . . . . . . . . . . . . . . . Nov. 2 . . . . . . . . . . . . . 21 94 66 79 0 379 Oct. 31 . . . . . . . . . . . . . . .. Nov. 20-21 . . . . . . . . . . 20.2 94 66 79 0 380 Oct 31-Nov 1 . . . . . . . .. Nov. 21 . . . . . . . . . . . .. 20.8 94 66 79 0 381 Nov 1-2 . . . . . . . . . . . . .. Nov. 21-22 . . . . . . . . . . 20.1 94 66 79 0 382 Nov 3 . . . . . . . . . . . . . . . Nov. 24 . . . . . . . . . . . . . 21 94 66 79 7 *383 Nov 3-4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 384 Nov 4 . . . . . . . . . . . . . . . Nov 5 . . . . . . . . . . . . . 21 94 66 80.1 385 Nov 5 . . . . . . . . . . . . . .. Nov 26-Dec 3 22 3 94 64 78.5 386 Nov 6 . . . . . . . . . . . . . . . Nov. 28-3 . . . . . . . . . . 22 6 94 66 79.5 387 Nov 7 . . . . . . . . . . . . . .. Dec. 1-4 . . . . . . . . . . .. 26 94 64 78.2 388 Nov 8 . . . . . . . . . . . . . .. Dec. 4 . . . . . . . . . . . .. 26 94 64 78.1 389 Nov . . . . . . . . . . . . . . . Dec. 5 . . . . . . . . . . . . . 26 92 64 77.6 390 Nov 10 . . . . . . . . . . . . . .. Dec. 6 . . . . . . . . . . . .. 26 88 64 77.4 391 Nov 10 . . . . . . . . . . . . . .. Dec. 6 . . . . . . . . . . . .. 26 88 64 77.4 392 Nov 11 . . . . . . . . . . . . . .. Dec. 8 . . . . . . . . . . . .. 27 94 64 77.8 393 Nov 12 . . . . . . . . . . . . . .. Dec. 8 . . . . . . . . . . . .. 26 94 64 77.8 394 Nov 13 . . . . . . . . . . . . . . . Dec. . . . . . . . . . . . . . 26 94 60 78.0 395 Nov 14 . . . . . . . . . . . . . . . Dec. 1O . . . . . . . . . . . . . 26 94 60 78.1 396 Nov 15 . . . . . . . . . . . . . . . Dec. 11 . . . . . . . . . . . . . 26 94 60 77.9 397 Nov 16 . . . . . . . . . . . . . . . Dec. 12 . . . . . . . . . . . . . 26 94 60 78.0 398 Nov 1 . . . . . . . . . . . . . . . Dec. 13 . . . . . . . . . . . . . 26 94 60 77.6 399 Nov 18-20 . . . . . . . . . . . . Dec. 18 . . . . . . . . . . . .. 28 4 94 60 76.7 400 Nov 1 . . . . . . . . . . . . . . . Dec. 19 . . . . . . . . . . . . . 28 94 60 76.7 401 Nov 22 . . . . . . . . . . . . . . . Dec. 20 . . . . . . . . . . . . . 28 94 60 76.9 402 Nov 24 . . . . . . . . . . . . . . . Dec. 22 . . . . . . . . . . . . . 28 94 60 76.6 403 Nov . . . . . . . . . . . . . . . Dec. 23 . . . . . . . . . . . . . 29 94 60 76.8 404 Nov 5 . . . . . . . . . . . . . . . Dec. 24 . . . . . . . . . . . . . 29 94 60 76.5 405 Nov 25-26 . . . . . . . . . . . . Dec. 24-25 . . . . . . . . . . . 28 3 94 60 76.4 406 Nov 6 . . . . . . . . . . . . . . . Dee 25 . . . . . . . . . . . . . 29 94 6O 76.1 407 Nov 8 . . . . . . . . . . . . . .. Dec 26-27 . . . . . . . . . .. 28 5 94 56 76.0 408 Nov 29-30 . . . . . . . . . . . . Dec. 27 . . . . . . . . . . . . . 27 7 94 56 76.0 409 Dec 1 . . . . . . . . . . . . . . . Dec. 29 . . . . . . . . . . . . . 28 94 56 76.6 410 Dec 2 . . . . . . . . . . . . . .. Dec. 3O . . . . . . . . . . . . . 28 94 56 77.0 411 Dec 3 . . . . . . . . . . . . . . . Dec. 31. . . . . . . .. 28 94 56 76.9 412 Dec. 4 . . . . . . . . . . . . . . . Jan. 1 . . . . . . . . . . . . .. 28 94 56 78.1 413 Dec. 4-5 . . . . . . . . . . . . .. Jan. 2 . . . . . . . . . . . . .. 28.2 94 56 78.1 414 Dec. 5 . . . . . . . . . . . . . .. Jan. 3 . . . . . . . . . . . . .. 29 94 56 78.0 415 Dec. 6 . . . . . . . . . . . . . .. Jan. 4 . . . . . . . . . . . . .. 29 94 56 77.9 416 Dec. 6-7 . . . . . . . . . . . . . . Jan. 4-5 . . . . . . . . . . . . 28.2 94 56 77.8 417 Dec. 7. . . .- . . . . . . . . . .. Jan. 5-6 . . . . . . . . . . . .. 28.2 93 56 77.3 418 Dec. 8 . . . . . . . . . . . . . .. Jan. 6 . . . . . . . . . . . . .. 29 93 56 77.2 419 Dec. 10 . . . . . . . . . . . . . .. Jan. 7 . . . . . . . . . . . . . . 28 93 56 77.0 420 Dec. 11 . . . . . . . . . . . . . .. Jan. 7-8 . . . . . . . . . . .. 27.6 93 56 77.1 421 Dec. 12 . . . . . . . . . . . . . .. Jan. 8 . . . . . . . . . . . . . . 27 93 56 77.4 422 Dec. 13 . . . . . . . . . . . . . .. Jan. 9-10 . . . . . . . . . .. 28.2 93 56 76.8 423 Dec. 14 . . . . . . . . . . . . . . . Jan. 10-11 . . . . . . . . . . . 28.1 93 56 77.9 424 Dec. 15 . . . . . . . . . . . . . .. Jan. 11-12 . . . . . . . . . .. 27.8 93 56 78.4 425 Dec. 16 . . . . . . . . . . . . . .. Jan. 13 . . . . . . . . . . . . .. 28 93 56 78.8 426 Dec. 18 . . . . . . . . . . . . . .. Jan. 14-15 . . . . . . . . . . . 27.5 93 56 79.2 427 Dec. 18 . . . . . . . . . . . . . . . Jan. 16 . . . . . . . . . . . . . 29 95 56 79.5 428 Dec. 19 . . . . . . . . . . . . . .. Jan. 17 . . . . . . . . . . . . . . 29 96 56 79.6 429 Dec. 20 . . . . . . . . . . . . . . . Jan. 18-19 . . . . . . . . . . . 29.8 96 56 79.9 430 Dec. 22 . . . . . . . . . . . . . . . Jan. 20 . . . . . . . . . . . . . 29 96 56 79.7 431 Dec. 23 . . . . . . . . . . . . . . . Jan. 21 . . . . . . . . . . . . . . 29 96 56 79.6 432 Dec. 24 . . . . . . . . . . . . . . . Jan. 22-23 . . . . . . . . . . . 29.2 96 56 79.7 433 Dec. 26 . . . . . . . . . . . . . . . Jan. 24 . . . . . . . . . . . . . . 29 96 56 80.3 434 Dec. 29 . . . . . . . . . . . . . . . Jan. 26 . . . . . . . . . . . . . . 28 96 70 80.1 435 Dec. 30 . . . . . . . . . . . . . . . Jan. 27 . . . . . . . . . . . . . . 28 96 70 79.9 436 Dec. 31. . . . . . . . . . . Jan. 27-28 . . . . . . . . . . . 27.2 96 70 79.6 437 Jan. 2 . . . . . . . . . . . . . . . . Jan. 28 . . . . . . . . . . . . . . 26 96 70 79.4 438 Jan. 3 . . . . . . . . . . . . . . . Jan. 29 . . . . . . . . . . . . . 26 96 64 79.3 439 Jan. 4 . . . . . . . . . . . . . . . . Jan. 30 . . . . . . . . . . . . . . 26 96 64 79.2 440 Jan. 5-6 . . . . . . . . . . . . .. Jan. 30 . . . . . . . . . . . .. 24.4 96 ’ 64 79.3 441 Jan. 7 . . . . . . . . . . . . . . .. Feb. 2 . . . . . . . . . . . . . - 26 96 64 80.0 442 Jan. 8 . . . . . . . . . . . . . . . . Feb. 3 . . . . . . . . . . . . . 26 96 64 80.3 443 Jan. 11 . . . . . . . . . . . . . . . . Feb. 5 . . . . . . . . . . . . . 25 96 64 80.8 444 Jan. 12 . . . . . . . . . . . . . . . . Feb. 6 . . . . . . . . . . . . . 25 96 ‘ 64 v 81.0 445 Jan. 13 . . . . . . . . . . . . . . . . Feb. 7 . . . . . . . . . . . . . 25 96 64 81.0 446 Jan. 14 . . . . . . . . . . . . . . . . Feb. 9 . . . . . . . . . . . . . 26 96 64 80.5 447 . Jan. 15 . . . . . . . . . . . . . . . . Feb. 10 . . . . . . . . . . . . . 26 96 64 80,2 448 . Jan. 16 . . . . . . . . . . . . . . .. Feb. 10-11 . . . . . . . . . .. 25.6 96 64 80.0 449 Jan. 17 . . . . . . . . . . . . . . .. Feb. 10 . . . . . . . . . . . .. 24 96 64 79.7 *450 Jan. 18 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 451 Jan. 19 . . . . . . . . . . . . . . .. Feb. 12 . . . . . . . . . . . .. 24 95 64 79.0 ' Incomplete record. 30 BULLETIN N0. 308. Table 5--Duration of larval stage—C0ntinued Average Temperature Lot Hatched Pupatcd period, days Max I Min. Mean 1920 1920 452 Jan 2O . . . . . . . . . . . . . . . . Feb. 12-18 . . . . . . . . . . . 26 95 58 77.2 453 Jan 1 . . . . . . . . . . . . . . . . Feb. 1 . . . . . . . . . . . . . 28 95 58 76.8 454 Jan 22-23 . . . . . . . . . . . . . Feb. 19-20 . . . . . . . . . . . 28.2 95 58 76.9 455 Jan 4 . . . . . . . . . . . . . . . . Feb. 21 . . . . . . . . . . . . . 28 95 58 76.9 456 Jan 26 . . . . . . . . . . . . . . . . Feb. 2 . . . . . . . . . . . . . 27 95 58 77.2 457 Jan 27 . . . . . . . . . . . . . . . . Feb. 22-23 . . . . . . . . . . . 26.5 95 58 77.3 458 Jan 28 . . . . . . . . . . . . . . .. Feb. 23 . . . . . . . . . . . . . 26 95 58 77.4 459 Jan. 30 . . . . . . . . . . . . . . . . Feb. 26 . . . . . . . . . . . . . 27 95 58 77.4 460 Jan. 31 . . . . . . . . . . . . . . . . Feb. 26 . . . . . . . . . . . . . 26 95 58 77.3 461 Feb. 1 . . . . . . . . . . . . . . . Feb. 27 . . . . . . . . . . . . . 26 95 58 76.8 462 Feb. 2 . . . . . . . . . . . . . . . Feb. 28 . . . . . . . . . . . . . 26 95 58 76.3 463 Feb. 3 . . . . . . . . . . . . . .. March 1 27 90 58 75.3 464 Feb. 4 . . . . . . . . . . . . . . . March 2 . . . . . . . . . . . 27 9O 58 74.8 465 Feb. 5 . . . . . . . . . . . . . . . March 4 . . . . . . . . . . . 28 90 58 74.4 466 Feb. 6 . . . . . . . . . . . . . . . March 6 29 88 58 73 5 467 Feb. 7 . . . . . . . . . . . . . . . March 7 . . . . . . . . . . . . 29 88 58 73.0 468 Feb. 8 . . . . . . . . . . . . . . . March 8 . . . . . . . . . . . 29 88 55 72.4 469 Feb. 9 . . . . . . . . . . . . . . . March 10 . . . . . . . . . . . 30 90 55 72.5 470 Feb. 10 . . . . . . . . . . . . . .. March 12 . . . . . . . . . . . . 31 91 55 73.1 471 Feb. 11 . . . . . . . . . . . . . .. March 13 . . . . . . . . . .. 31 92 55 73.4 472 Feb. 12 . . . . . . . . . . . . . .. March 31 92 55 73.6 473 Feb. 12-13 . . . . . . . . . . . . . March 14-15 . . . . . . . . . 31 92 55 73.8 474 Feb. 13 . . . . . . . . . . . . . .. March 15 . . . . . . . . . . . 31 92 55 73.8 475 Feb. 16 . . . . . . . . . . . . . . . March 14-18 . . . . . . . . . 30.5 92 55 75.0 476 Feb. 16 . . . . . . . . . . . . . .. March 18-19 . . . . . . . . . 30.6 92 55 75.3 477 Feb. 17 . . . . . . . . . . . . . . . March 20 . . . . . . . . . . . . 32 92 55 75.6 478 Feb. 17-18 . . . . . . . . . . . . . March 21-22 . . . . . . . . . 32.6 92 55 75.8 479 Feb. 18 . . . . . . . . . . . . . .. March 33 92 55 75.8 480 Feb. 19 . . . . . . . . . . . . . . . March 23-24 . . . . . . . . . 33.3 92 55 76.0 481 Feb. 2O . . . . . . . . . . . . . . . March 25-26 . . . . . . . . . 34.2 92 55 76.6 482 Feb. 21 . . . . . . . . . . . . . . . March 27-28 . . . . . . . . . 35.5 92 55 76.5 483 Feb. 22 . . . . . . . . . . . . . . . March 28 . . . . . . . . . . . 35 92 55 76.4 484 Feb. 23 . . . . . . . . . . . . . . . March 29 . . . . . . . . . . . 35 92 55 76.4 485 Feb. 24 . . . . . . . . . . . . . . . March 30 . . . . . . . . . . . 35 92 55 76.3 486 Feb. 25 . . . . . . . . . . . . . . . March 31-April 1.. . . . 35.5 92 55 76.4 487 Feb. 26 . . . . . . . . . . . . . . . April 1-2 . . . . . . . . . . . 35.6 92 55 76.6 488 Feb. 27 . . . . . . . . . . . . . . . April 2 . . . . . . . . . . . . . 35 92 55 76.7 489 Feb. 28 . . . . . . . . . . . . . . . April 3. . . . . . . . . . . . . 35 92 55 76.9 480 March 1 . . . . . . . . . . . . . . April 4 . . . . . . . . . . . . . 34 92 55 77.5 491 March 4 . . . . . . . . . . . . . . pril 5-6 . . . . . . . . . . . 32.5 92 55 77.7 492 March 5 . . . . . . . . . . . . . . April 6-7 . . . . . . . . . . . 32.5 92 55 78.0 493 March 6 . . . . . . . . . . . . . April . . . . . . . . . . . . . 33 92 55 78.5 494 March 8 . . . . . . . . . . . . . . April . . . . . . . . . . . . . 32 92 62 79.8 495 March 1O . . . . . . . . . . . . . . April 10 . . . . . . . . . . . . . 31 92 68 80.0 496 March 11 . . . . . . . . . . . . . . April 10 . . . . . . . . . . . . . 30 92 68 80.0 *497 March 12 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 498 March 13 . . . . . . . . . . . . . . April 9 . . . . . . . . . . . . . 27 92 68 79.5 499 March 14 . . . . . . . . . . . . . . April 10 . . . . . . . . . . . . . 27 87 68 79.4 500 March 15 . . . . . . . . . . . . . . April 11 . . . . . . . . . . . . . 27 87 68 79.5 501 March 16 . . . . . . ; . . . . . . . April 12 . . . . . . . . . . . . . 27 87 68 79.5 502 March 17 . . . . . . . . . . . . . . April 13 . . . . . . . . . . . . . 27 87 68 79.4 503 March 17 . . . . . . . . . . . . . April 13 . . . . . . . . . . . . . 27 87 68 79.4 504 March 18 . . . . . . . . . . . . . April 14 . . . . . . . . . . . . . 27 87 68 79.0 505 March 19 . . . . . . . . . . . . . . April 15 . . . . . . . . . . . . . 27 87 68 78.9 506 March 23 . . . . . . . . . . . . . . April 16 . . . . . . . . . . . . . 24 87 68 78.8 507 March 24 . . . . . . . . . . . . . . April 17 . . . . . . . . . . . . . 24 94 68 79. 1 508 March 25 . . . . . . . . . . . . . . April 18 . . . . . . . . . . . . . 24 94 68 79.5 509 March 26 . . . . . . . . . . . . . April 19 . . . . . . . . . . . . . 24 94 68 79.6 510 March 28 . . . . . . . . . . . . . . April 22 . . . . . . . . . . . . . 25 94 68 80.1 511 March 29 . . . . . . . . . . . . . . April 23 . . . . . . . . . . . . . 25 94 68 80.3 512 March 29 . . . . . . . . . . . . . . April 23 . . . . . . . . . . . . . 25 94 68 80.3 513 March 30 . . . . . . . . . . . . . . April 24 . . . . . . . . . . . . . 25 94 68 80.7 514 March 31 . . . . . . . . . . . . . . April 25 . . . . . . . . . . . . . 25 94 68 81 . 1 *5l5 , April . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 516 April 1-3 . . . . . . . . . . . . . April 26-27 . . . . . . . . . . 23.8 94 68 81.0 517 April 4 . . . . . . . . . . . . . . . April 28 . . . . . . . . . . . . . 24 94 68 81 . 1 518 April 5 . . . . . . . . . . . . . . . April 29 . . . . . . . . . . . . . 24 94 71 81 .5 519 April 6 . . . . . . . . . . . . . . . April 30 . . . . . . . . . . . . . 24 94 73 81.8 520 April 8 . . . . . . . . . . . . . . . May 1 . . . . . . . . . . . . . 23 94 73 81.3 521 April 9 . . . . . . . . . . . . . . . April 30 . . . . . . . . . . . . . 21 94 73 82. 1 522 April l0 . . . . . . . . . . . . . .. May 1 . . . . . . . . . . . . . 21 94 73 82.2 523 April 15 . . . . . . . . . . . . . . . April 30-May 1 . . . . . . 15.3 94 73 83.0 524 April 17 . . . . . . . . . . . . . . . May 3-4 . . . . . . . . . . .. 16.6 94 73 83.5 525 April 2O . . . . . . . . . . . . . . . May . . . . . . . . . . . . . 16 94 73 83.8 *1 ncomplete record. THE SWEET POTATO WEEVIL. 31 A thermograph was used to record the existing temperatures during the time of observation. For each period the single highest tempera- ture and the single lowest temperature are given. The mean tempera- ture given is the average of the daily mean temperatures during the period. The shortest larval period, 10 days, occurred twice during August, 1919. The mean temperatures during these periods ranged from 86.8 to 87 degrees F. The longest larval period was 35.6 days. It occurred from February 26, 1920 to April 2, 1920. The mean temperature during this period was 76.6 degrees F. The yearly variation in the duration of the larval stage is shown in Table 6. The effect of the mean temperature on the length of the stage is apparent. During the winter months the period is more variable. A slight decrease in the mean temperature usually results in a consid- erable increase in the length of the period. Table 6 Yearly Variation in Duration of Larval Stage Date Period, Temperature, days mean May, 1918 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 14.3 78.4 May, 1919 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 17.1 84.7 June, 1918 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .I . . . . . . . . .. 15.3 94.0 June, 1919 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14.4 85.2 December, 1918 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .._ . . . . . . . . . . .. 24.8 81 .6 December, 1919 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28.3 76.9 January, 1919 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 22.2 79.1 January, 1920 . . . . . . . . . . . .- . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26.0 79.1 A summary of the duration of the larval stage from May, 1918 to April, 1920 is given in Table '7. The longest period and the shortest period for each month are given, together with the average period for the month. The average monthly period is the sum of the daily ob- servations divided by the number of collections of larvae on which notes were taken during the month. Table 7 Summary of Duration of Larval Stage Collections Month Temperature, Longest Shortest Average of larvae mean period period period observed 1918 May . . . . . . . . . . . . . . . .. 78.4 16 13 14.3 34 June . . . . . . . . . . . . . . . .. 94 .0 18.8 12 15.3 30 Decembeiigig . . . . . . . .. 81.6 25.6 24.3 24.8 5 January . . . . . . . . . . . . .. 79.1 25.6 19.1 22.2 33 February . . . . . . . . . . . .. 78.8 25.3 19.9 22.5 26 March . . . . . . . . . . . . . . . 80.4 28.2 23.8 26.6 29 April . . . . . . . . . . . . . . .. 82.4 25.2 19 21.4 33 ay . . . . . . . . . . . . . . . .. 84.7 20.7 14 17.1 31 June . . . . . . . . . . . . . . . .. 85.2 16.3 11.7 14.4 32 July . . . . . . . . . . . . . . . .. 92.3 14.6 10.3 12.8 30 August . . . . . . . . . . . . . . . 90.8 17 10 11 .8 30 September . . . . . . . . . . . . 85.1 19 .2 11 14 .7 26 October . . . . . . . . . . . . . . 84. 5 23 .7 20 21 .4 31 November . . . . . . . . . . . . 79 . 0 29 20 . 1 26 . 1 27 Decembtlaiééb . . . . . . . . . . 76 .9 29 .8 27 28 .3 28 January . . . . . . . . . . . . . . 79 . 1 28 .2 24 .4 26 23 February . . . . . . . . . . . . . 76.6 35 .6 26 31 . 1 29 March . . . . . . . . . . . . . . . 77 . 0 34 24 27 . 6 24 April . . . . . . . . . . . . . . .. 80.7 23.8 14.3 20.7 10 32 i BULLETIN No. 308. _ For the entire observations the longest period and the shortest period averaged 24 and 18.6 days, respectively. The mean temperature for the period over which the records were made averaged 82.4 degrees F. Prepupal Stage The duration of this stage usually extends from one to several days. It is characterized by the larva’s becoming shorter and distended, with the wrinkles onthe body more exaggerated. The thoracic region is greatly thickened, and the legs are represented by enlarged swellings. During this stage the larva remains quiet, but if disturbed, exhibits about the same. degree of activity as the pupa. The head is much narrower than the thorax and abdomen, and is yellowish-brown in color; The thorax and abdomen are white in color, the latter being modified somewhat in some specimens by dark abdominal contents, which show through the transparent body walls. The average length of this stage is about 5.5 mm. PTJlPLZttOTL The adult appendages are formed completely within the last larval skin, and the first external indication of pupation is the splitting of the head shield at the suture between the eyes, and skin on the dorsum of the thorax. Through this split soon appears the white head and thorax of the pupa. The head shield is pushed backward over the head and beak on the ventral side of the thorax. At this time the antennae are geniculate with the distal portion bent posteriorly; however, they soon straighten out and are almost in normal position by the time pupation has been completed. When the head, beak, and thorax are exposed, the last larval skin is slowly pushed backward over the tip of the abdomen by a series of body contractions and vigorous twistings and lateral movements. The newly transformed pupa is fully developed, and clear White in color. The cast skin sometimes remains attached to the tip of the abdomen for a brief period, but normally it is cast off com- pletely during the process of pupation. The head shield remains at- tached to the cast larval skin. The time required for pupation varies considerably and on the average consumes thirty to forty-five minutes. Papa Desoriptionr-The pupa is at first white, b-ut shortly before its trans- formation to the adult, it becomes yellowish and then gradually grows darker in color. t a Ventral view: Elongate, tapering to a blunt point posteriorly, broad; ly rounded anteriorly. Head and beak elongate, folded down upon the thorax. The beak robust and extends between the first pair of legs slightly beyond the first tarsal joint. Both head and beak bear several pairs of minute tubercles with long slender bristles or hairs. The eyes at first colorless, but grow darker with age, and become dark-brown, or almost black before transformation to adult. The antennae extend anteriorly towards and beyond the dorsum, not folded; the segments distinct, and the last one bears numerous minute tubercles. The legs not folded, lying closely upon the body, and extending posteriorly. The first two pairs plainly visible, with the segments distinct. The hind THE SWEET Porno WEEVIL. 33 pair covered by the wing pads except the tarsal joints, which reach to the base of the seventh abdominal segment. The abdomen is mobile. On the distal end two prominent pointedprongs directed posteriorly and curved outward. These processes assist in the rather limited lateral movements which the pupa is able to make. The abdominal segments distinct and become smaller posteriorly; all strongly wrinkled; on the lateral margin of each segment prominent tubercles bearing short hairs. Lateral view: The dorsum gently convex when pupa is in natural position. The head deflexed. Thoracic segments distinct, all bearing tuberculate hairs on dorsum. Prothorax strongly convex on dorsum, prominent; antennae and first two pairs of legs situated closely upon sides of the thorax and extending diagonally to the body. Several short hairs on the knees of each pair of legs. The tips of the antennae extending above the dorsum of thorax. Elytra striate. Wings promi- nent, directed backward and downward, extending between the second and third pair of legs. The last pair, except the "knees and tarsi, en- tirely covered by the wings. Abdominal segments distinct, wrinkled on the dorsum, with many small tubercles on each segment bearing short hairs. Spiracles not conspicuous. Dorsal view: Head with eight long hairs, each originating from a minute tubercle. Front margin of prothorax with four similar hairs, and several short discal bristles on mesothorax. Tips of the antennae on each side of prothorax prominent. The knees of all legs plainly visible; the last pair between the wings and body. Abdominal seg- ments become smaller posteriorly; each with a discal row of very small tubercles bearing setae of varying lengths. Views of the pupa are shown in Figure 3. The pupa averages about 5 mm. in length, and 1.5 mm. in width. Measurements of twenty individuals are given in Table 8.. a Table 8 Measurements of Pupa Length, Width, mm. mm. Average . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 5.2 1.6 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 5.5 1.5 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 5.2 1.5 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 5.0 1.2 4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 5.2 1.5 5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 4.8 1.4 6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 5.7 2.0 7 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 5.0 1.5 8 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 4.5 1.4 9 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 5.5 1.8 10 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 5.5 2.0 A 11 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 5.5 2.0 12 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 5.0 1.7 13 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . , . . . . . .. 5.2 1.3 A 14 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 5.5 1.5 15 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 5.5 2.0 ~ 16 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 4.5 1.5 17 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 5.5 2.0 18 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 5.0 1.6 19 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 5.3 1.4 20 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 5.2 1.5 34 . BULLETIN N0. 308. Duration of the Papa-Z Stage It was determined that the pupa would complete its development if removed from the pupal cell and kept in a small tin box containing a bit of moistened cotton. The observations on the length of the pupal stage made in this manner did not vary greatly from those where the pupa was allowed to develop within the tuber. The former method, however, does not include the time elapsing from transformation to adult emergence. All observations given here on the length of the pupal stage Were made on pupae within the tuber, and the termination of the stage was considered as the emergence of the adult. This makes the stage slightly longer on the average, but gives the exact time re- quired from egg deposition to appearance of the adult of the next generation. The data obtained in laboratory observations from May, 1918 to May, 19.20, are given in Table 9. It will be noted that there is eon- siderable variation in the length of this stage during some seasons. This is very likely caused by varying eifective temperatures and the condition of the tubers. The longest pupal period, 27.8 days, was noted in December, 1919, with a mean temperature of 76.9 degrees F. The maximum temperature and the minimum temperature that oc- curred during this period were 96 and 56 degrees F., respectively. The shortest pupal period, 7 days_, occurred in May, 1918. The mean for this period was 82.3 degrees F. Table 9 Duration of Pupal Stage Average Temperature Lot Pupated Emerged period, No. days Max. Min. Mean 1918 1918 1 May 20-22 . . . . . . . . . . . .. May 27-29. . . . . . . . . .. 7 87 74 82.3 2 May 21-22 . . . . . . . . . . . . . May 29-June 2 . . . . . . . 9 89 74 83.1 3 May 21-23 . . . . . . . . . . . . . May 30-31 . . . . . . . . . . . 9 89 74 82.8 4 May 22-23 . . . . . . . . . . . . . May 30-June 1 . . . . . . . 9.2 89 74 83.1 5 May 21-23 . . . . . . . . . . . . . May 30-31 . . . . . . . . . . . 9.4 89 74 82.8 6 May21-24............. May30-June2 . . . . . .. 9.2 89 74 83.1 7 May 22-23 . . . . . . . . . . . .. June 3 . . . . . . . . . . . .. 11 .3 89 74 83.2 8 May 23 . . . . . . . . . . . . . .. June 1-3 . . . . . . . . . .. 10 89 74 83.3 9 May24 . . . . . . . . . . . . . ..June 1-2............ 8.7 89 75 83.6 10 May 23-27 . . . . . . . . . . . . . June 2-4 . . . . . . . . . . . . 9.7 89 74 83.2 11 May 24 . . . . . . . . . . . . . .. June 2-3 . . . . . . . . . . .. 9.5 89 75 83.5 12 May25 . . . . . . . . . . . . . ..June 3-7............ 10 89 75 83.5 13 May 27 . . . . . . . . . . . . . .. June 3-10 . . . . . . . . . . . 9.2 97 77 86.8 14 May 27-28 . . . . . . . . . . . . June 3-10 . . . . . . . . . . . 9.8 97 77 86.8 15 May 28-29 . . . . . . . . . . . . . June 5-10 . . . . . . . . . . . 9.8 97 77 87.3 16 May 29-31 . . . . . . . . . . . . . June 6-10 . . . . . . . . . .. 9.6 97 77 87.7 17 May 30-31 . . . . . . . . . . . .. June 7-16 . . . . . . . . .. 11 .1 102 77 90.1 18 May 31-June 1 . . . . . . . . . June 9-12 . . . . . . . . . .. 9.8 100 77 88.9 19 May 31-June 1 . . . . . . . . . June 10-12 . . . . . . . . . .. 10.3 100 77 88.9 20 June 1-2 . . . . . . . . . . . . ..June10-11........... 8.8 98 77 88.5 21 June 2-4 . . . . . . . . . . . . . . June 11-16 . . . . . . . . . .. 10.1 102 77 91.3 22 June 3-4 . . . . . . . . . . . . .. June 11-18 . . . . . . . . . .. 9.5 102 79 91.0 23 June 3-5 . . . . . . . . . . . . . . June 11-19 . . . . . . . . . .. 11.4 107 81 91.8 24 June 4-5 . . . . . . . . . . . . .. June 14-23........... 11.8 107 81 94.6 25 June 5 . . . . . . . . . . . . . . . June 13-21 . . . . . . . . . .. 11.7 107 81 94.9 26 June 6-7 . . . . . . . . . . . . .. June 15-20 . . . . . . . . . . 10.4 107 87 95.2 27 June 7-8 . . . . . . . . . . . . .. June 16-21...... 10.4 107 87 95.5 28 June 8-9 . . . . . . . . . . . . .. June 16-25. . .. . . . . . .. 9.7 107 87 96.2 29 June 9-10 . . . . . . . . . . . . . June 16-23 . . . . . . . . . . . 9.9 107 87 96.1 30 June 10 . . . . . . . . . . . . . .. June 17-22 . . . . . . . . . . . 9.1 107 87 96.0 31 June 10-12 . . . . . . . . . . . . . June 18-22 . . . . . . . . . . . 9.1 107 87 96.0 32 June 11-12 . . . . . . . . . . . . . June 18-25 . . . . . . . . . . . 9.4 107 88 96.9 33. June 13. . . .' . . . . . . . . . . . June 18-24 . . . . . . . . . . . 9 107 89 97.1 34 June 14 . . . . . . . . . . . . . .. June 22-24. . . . . . . . . .. 9 107 89 97.4 35 June 15 . . . . . . . . . . . . . June 21-25 . . . . . . . . . .. 8.5 107 89 97.6 36 June 16 . . . . . . . . . . . . . .. June 21-26 . . . . . . . . . .. 7.6 107 89 98.0 37 June 18 . . . . . . . . . . . . . . . June 26-27 . . . . . . . . . . . 8.7 107 93 98.8 38 June 18 . . . . . . . . . . . . . . . June 27-29 . . . . . . . . . . . 9.7 107 93 98.7 THE SWEET POTATO WEEVIL. 35 ‘Table 9-—Duration of Pupal Stage-Continued Average Temperature Lot Pupated Emerged period, No. days Max Min Mean 1918 1918 39 June 19 . . . . . . . . . . . . . .. June 29-30 . . . . . . . . .. 10.2 105 93 98.5 40 June 19 . . . . . . . . . . . . . .. June 29-30 . . . . . . . . . . 10.2 105 93 98.5 41 June 19-20 . . . . . . . . . . . .. June 29 . . . . . . . . . . . . . 9.6 105 93 98.5 42 June 20 . . . . . . . . . . . . . . . June 29-July 4 . . . . . . . 11.3 103 85 97.7 43 June 22 . . . . . . . . . . . . . .. July 2-7 . . . . . . . . . . .. 12 103 85 97.2 44 June 23 . . . . . . . . . . . . . . . July 4-7 . . . . . . . . . . . . 12.4 103 85 97.0 45 June 25-26 . . . . . . . . . . . . . Jul-y 5-9 . . . . . . . . . . . . 11.3 103 85 97.0 46 June 26 . . . . . . . . . . . . . .. July 7-14 . . . . . . . . . .. 13.3 106 84 97.2 47 June 28 . . . . . . . . . . . . . . . July 7-13 . . . . . . . . . . . 12 106 85 96.1 48 June 28-29............. July 9-11 . . . . . . . . . .. 11.5 106 85 97.2 49 June 30 . . . . . . . . . . . . . .. July 8-15 . . . . . . . . . .. 11.6 106 84 97.1 50 July . . . . . . . . . . . . . . . . uly 9-13 . . . . . . . . . . . 10.4 106 85 97.2 51 July 2-3 . . . . . . . . . . . . . . July 12-25 . . . . . . . . . . . 16.1 106 84 97.3 52 July 3-4 . . . . . . . . . . . . .. July 14 27 . . . . . . . . . .. 15 106 84 97.4 53 July 5 . . . . . . . . . . . . . . . . July 13-18 . . . . . . . . . .. 11.8 106 84 97.5 54 July 6 . . . . . . . . . . . . . . . . July 15-23 . . . . . . . . . . . 12.6 106 84 97.7 55 July 8 . . . . . . . . . . . . . . . . July 15-18 . . . . . . . . . .. 8 106 84 98.0 56 July 1O . . . . . . . . . . . . . . .. July 17-25 . . . . . . . . . .. 9.8 105 84 96.2 57 July 11 . . . . . . . . . . . . . . .. July 18-27 . . . . . . . . . .. 11.2 105 84 97.5 58 July 12-13 . . . . . . . . . . . . . July 22-28 . . . . . . . . . . . 11.3 105 84 97.4 59 uly 14 . . . . . . . . . . . . . . . July 20-23 . . . . . . . . . . . 10 105 90 97.6 60 July 14-15 . . . . . . . . . . . . . y 23-Aug. 1 . . . . . . . 14 105 88 97.3 *61 July 15 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . _ . . . . . . . . . . . . . *62 July 16 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63 July 17 . . . . . . . . . . . . . . . . July 24-Aug. 11 . . . . . . 14 105 88 96.8 64 July 16-18 . . . . . . . . . . . .. July 24-31 . . . . . . . . . .. 10.3 105 88 96.0 65 July 17-18 . . . . . . . . . . . . . July 25-Aug 1 . . . . . . . 11 105 88 96.0 66 July 15-19 . . . . . . . . . . . . . uly 25-2 . . . . . . . . . . . 9 105 90 97.6 67 July 17-19 . . . . . . . . . . . .. July 31-Aug 3 . . . . . . . 9.8 105 88 97.4 68 uly 2 . . . . . . . . . . . . . . . . uly 30-3 . . . . . . . . . . . 9.5 102 88 97.5 69 July 22. . . . . . . . . . . .. July 29-A1ugg 3 . . . . . .. 8.7 103 88 97.4 70 Jan. 20-21 . . . . . . . . . . . .. Feb 1-10 . . . . . . . . . . . 10.5 93 63 79.5 71 Jan 22-23 . . . . . . . . . . . . . Feb 4-8 . . . . . . . . . . . . 14.3 93 63 79.5 72 Jan. 22-25 . . . . . . . . . . . . . Feb 7-15 . . . . . . . . . . . 17.1 93 63 79.6 73 Jan. 25-26 . . . . . . . . . . . . . Feb 9-16 . . . . . . . . . . . 17.3 93 65 79.6 74 Jan. 26-27 . . . . . . . . . . . . . Feb 10-13 . . . . . . . . . . . 16.7 93 65 79.2 75 Jan. 26-27 . . . . . . . . . . . . . Feb 10-14 . . . . . . . . . . . 15.8 93 65 79.7 76 Jan. 27 . . . . . . . . . . . . . . .. Feb 11-14 . . . . . . . . . .. 16.7 93 65 79.8 77 Jan. 27-28 . . . . . . . . . . . . . Feb 12-14 . . . . . . . . . . . 16 93 65 79.8 78 Jan 30-31 . . . . . . . . . . . .. Feb 12-16 . . . . . . . . . . . 16 93 65 79.9 79 Jan 28-31 . . . . . . . . . . . .. Feb 13-18 . . . . . . . . . .. 15.9 93 65 80.2 80 Jan 30-Feb 2 . . . . . . . .. Feb 13-17 . . . . . . . . . .. 15 93 65 80.2 81 Jan . . . . . . . . . . . . . . .. Feb 14-17 . . . . . . . . . .. 15 93 65 79.9 82 Jan 31-Feb. 3 . . . . . . . . . Feb 16-18 . . . . . . . . . . . 15 93 65 79.8 83 Feb Feb 17-21 . . . . . . . . . .. 16.9 93 65 79.5 84 Feb. 3-9 . . . . . . . . . . . . .. Feb 17-20 . . . . . . . . . .. 12.8 93 65 79.8 85 Feb. 4-11 . . . . . . . . . . . . . Feb 20-27 . . . . . . . . . . . 15.5 93 63 79.0 86 Feb. 5-13 . . . . . . . . . . . .. Feb 20-23 . . . . . . . . . .. 14.3 93 63 79.7 87 Feb. 6-11 . . . . . . . . . . . . . Feb 20-25 . . . . . . . . . . . 14.5 93 63 79.5 88 Feb. 7-10 . . . . . . . . . . . . . Feb 19-24 . . . . . . . . . . . 14.3 93 63 79.4 89 Feb. 8-10 . . . . . . . . . . . .. Feb 22-25 . . . . . . . . . .. 14.8 93 63 79.4 90 Feb. 9-12 . . . . . . . . . . . .. Feb 22-26 . . . . . . . . . .. 15.5 93 63 79.6 91 Feb. 8-11 . . . . . . . . . . . .. Feb 24-27 . . . . . . . . . .. 16.4 93 63 79.7 92 Feb. 8-10 . . . . . . . . . . . . . Feb 25-26 . . . . . . . . . . . 16.5 93 63 79.6 93 Feb. 8-11 . . . . . . . . . . . .. Feb 5-28 . . . . . . . . . .. 17 93 63 79.8 94 Feb 10-17 . . . . . . . . . . . . . Feb 26-March 3. . . . . 15.9 93 63 80.5 95 Feb 11-14 . . . . . . . . . . . . . Feb 28-March 3. . . . . 17.4 93 63 80.7 96 Feb 13-19 . . . . . . . . . . . .. March 1-5 . . . . . . . . .. 15.4 101 63 81.8 97 Feb 14-27 . . . . . . . . . . . . . March 2-9 . . . . . . . . . . 17.1 101 63 81.5 98 Feb 15-19 . . . . . . . . . . . . . March 4-7 . . . . . . . . . . 15.9 101 63 81.8 99 Feb 15-18 . . . . . . . . . . . .. March 5-10 . . . . . . . .. 17.5 101 63 81.2 100 Feb 8-25 . . . . . . . . . . . . . March 5-9 . . . . . . . . . . 15.7 101 63 81.6 101 Feb 17-19 . . . . . . . . . . . . . March 4-12 . . . . . . . . . 17.5 101 63 81 .0 102 Feb 17-20 . . . . . . . . . . . .. March 7-11 . . . . . . . .. 17.5 101 63 81.0 103 Feb 18-23 . . . . . . . . . . . .. March 7-14 . . . . . . . .. 17.2 101 63 80.9 104 Feb 20-24 . . . . . . . . . . . . . March 8-23 . . . . . . . .. 17.5 101 63 80.5 105 Feb 1-28 . . . . . . . . . . . .. March 8-15 . . . . . . . .. 14.5 ‘ 101 63 80.9 106 Feb 24-March 5 . . . . . . . March 8-16 . . . . . . . . . 15.4 101 72 82.2 107 Feb. 25-March 2 . . . . . . . March 9-16 . . . . . . . . . 14.4 101 72 82.2 108 Feb 26-March 3 . . . . . . . March 9-16 . . . . . . . . . 14.5 101 72 82.2 109 Feb. 28-March 3 . . . . . . . March 16. . . . 14.5 101 72 82.2 110 March 1-4 . . . . . . . . . . . . March 16-22 . . . . . . . . . 16.2 101 71 ' 81 .2 111 March 2-6 . . . . . . . . . . . . March 16-25 . . . . . . . . . 18 101 71 80.9 112 March 1-8 . . . . . . . . . . . . March 16-25 . . . . . . . . . 17.7 101 71 80.9 113 March 1-8 . . . . . . . . . . .. March 16-24 . . . . . . . . . 16.2 101 71 81.0 114 March 3-7 . . . . . . . . . . . . March 15-20 . . . . . . . . . 15 101 72 80.9. 115 March 3-11 . . . . . . . . . . . March 17-24 . . . . . . . . . 66.1 101 71 80.5 ‘f! ncomp lete record. bdoL-babwkzbwioloboL-bvlaboi-Lokibbkai-Kolabo 36 BULLETIN N0. 308. Table]9--Duration“_of Pupal Stage-Continued Avera e Temperature Lot Pupated Emerged perio , _ N0. days Max. Mm. Mean 1919 1919 116 March 7-9 . . . . . . . . . . .. March 21-30. . . -. . . . .. 16.1 88 71 78 117 March 3-5 . . . . . . . . . . . . March 17-28 . . . . . . . . . 18 101 71 80 118 March 3-11 . . . . . . . . . . . March 20-30 . . . . . . . . . 19.9 101 71 8O 119 March 6-15 . . . . . . . . . .. March 24-April 2. . . .. 19.4 90 71 79 120 March 5-15 . . . . . . . . . . . March 25-April 2. . . . . 19.5 90 71 79 121 March 7-16 . . . . . . . . . . . March 26-31 . . . . . . . . . 18.2 88 71 79 122 March 9-12 . . . . . . . . . . . March 26-April 3. . . . . 17.9 88 71 79 123 March 9-12 . . . . . . . . . . . March 28-April 4. . . . . 19 88 71 78 124 March 10-12 . . . . . . . . . . . March 29-30 . . . . . . . . . 18.4 88 71 78 125 March 11-16 . . . . . . . . . .. March 29-April 1.. . .. 17.9 88 71 79 126 March 12-17 . . . . . . . . . . . March 30-April 6.. . . . 19.1 88 71 78 127 March 14-21 . . . . . . . . . . . March 31-April 9.. . . . 19.6 88 71 79 128 March 14 23 . . . . . . . . t . . April 4-11 . . . . . . . . . . 21.1 88 70 79 129 March 16-22 . . . . . . . . . .. April 1-8 . . . . . . . . . .. 18.7 88 71 ~ 79 130 March 18-24 . . . . . . . . . . . April 7-14 . . . . . . . . . . 20.2 95 7O 79 131 March 21-25 . . . . . . . . . . . April 8-13 . . . . . . . . . . 19.7 93 7O 79 132 March 22-25 . . . . . . . . . . . April 9-14 . . . . . . . . . . 19.2 95 70 80 133 March 22-26 . . . . . . . . . . . April 9-16 . . . . . . . . . . 19.6 95 7O 80 134 March 24-28 . . . . . . . . . . . April 12-16 . . . . . . . . . . 18.8 95 7O 80 135 March 28-April 6 . . . . . . . April 13-20 . . . . . . . . . . 17.4 95 70 81 136 March 29-April 1 . . . . . . . April 14-19 . . . . . . . . . . 18.2 95 70 81 137 March 30-April 4 . . . . . . . April 16-24 . . . . . . . . . . 18.1 95 7O 82 138 March 31-April 4 . . . . . . . April 16-23 . . . . . . . . . . 17.9 95 7O 82 April 1-6 . . . . . . . . . . . . . April 17-25 . . . . . . . . . . 18 95 70 82 *141 April 2-9 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 142 April 3-11 . . . . . . . . . . . . April 24-26 . . . . . . . . . . 19.2 95 7O 83.0 143 April 5-11 . . . . . . . . . . . . April 23-28 . . . . . . . . . . 18.2 95 70 83.5 144 April 7-9 . . . . . . . . . . . . . April 26-27 . . . . . . . . . . 18.4 95 7O 83.3 145 April 7-12 . . . . . . . . . . . . pril 27 . . . . . . . . . . . . . 18.4 95 7O 83.3 146 April 9-18 . . . . . . . . . . . . April 28 . . . . . . . . . . . . . 18.5 95 7O 83.5 147 April 8-13 . . . . . . . . . . . . April 27-29 . . . . . . . . . . 16.5 95 70 83.7 148 April 9-19 . . . . . . . . . . . . April 27-30 . . . . . . . . .. 16 95 7O 83.7 149 April 10-16 . . . . . . . . . . . . pril 29-30 . . . . . . . . . . 16 95 7O 83.9 150 April 14-20 . . . . . . . . . . . . April 29-May 2.. . . . . . 16.3 93 72 84.1 151 Apfll 13-17 . . . . . . . . . . . . April 30- ay 2 . . . . . . 16 95 72 84.3 152 April 15-19 . . . . . . . . . . .. May 1-2............ 15.7 93 72 84.1 153 April 17-18 . . . . . . . . . . .. May 1-9. . 17.3 93 75 84.0 154 April 17-24 . . . . . . . . . . . . May 2-6 . . . . . . . . . . . 15.8 93 75 84.9 155 April 19-21 . . . . . . . . . . . . May 2-10 . . . . . . . . . . . 14.6 93 75 83.9 156 April 19-20 . . . . . . . . . . . . May 4-7 . . . . . . . . . . . . 15 .3 93 75 84.9 157 April 19-21 . . . . . . . . . . . . May 4-9 . . . . . . . . . .. 15.8 93 75 84.2 158 April 21-25 . . . . . . . . . . .. May 5-6. . . . 14.5 93 76 84.6 159 April 22-26 . . . . . . . . . . . . May 7-11. . . 13.3 93 71 83.3 160 April 23-25 . . . . . . . . . . . . May 6-14 . . . . . . . . . . . 14.8 94 71 83.3 161 April 25-27 . . . . . . . . . . . . May 7-11. . 13 93 71 83.2 162 April 25-28 . . . . . . . . . . . . May 8-10.. 13 93 75 83.7 163 April 26-28 . . . . . . . . . . .. May 9-16.. 16 97 71 83.9 164 April 27-28 . . . . . . . . . . . . May 9-14 . . . . . . . . . . . 15 94 71 83.2 165 April 26-30 . . . . . . . . . . . . ay 9-17 . . . . . . . . . . 14 100 71 84.3 166 April 28-29 . . . . . . . . . . . . May 10-16 14.7 97 71 83.1 167 April 29-30 . . . . . . . . . . . . May 10-20 . . . . . . . . . . 15.4 100 71 84.4 168 April 30-May 1 . . . . . . . . May 10-1 14. 1 100 71 84.1 169 April 27-30 . . . . . . . . . . . . May 10-17 . . . . . . . . . . . 15.8 100 71 84.4 170 April 29-30 . . . . . . . . . . . . May 12-18 . . . . . . . . . . 15.3 100 71 84.3 171 May 1-2 . . . . . . . . . . . .. May 13-28 . . . . . . . . . .. 15.5 100 71 84.8 172 May 1-3 . . . . . . . . . . . . .. ay 15-18 . . . . . . . . . .. 15.7 100 71 84.5 173 May 2-3 . . . . . . . . . . . . .. ay 17-21 16 100 71 84.5 174 May 2-4 . . . . . . . . . . . . .. May 15-24 . . . . . . . . . .. 15.3 100 71 84.7 175 May 3-4 . . . . . . . . . . . . . . May 14-19 . . . . . . . . . . . 14.7 100 71 84.3 176 May 3-5 . . . . . . . . . . . . .. ay 18-23 16.4 100 71 84.4 177 May 4-5 . . . . . . . . . . . . .. May 18-24 . . . . . . . . . .. 15.3 100 71 84.4 178 May 4-5 . . . . . . . . . . . . . May 18-27 . . . . . . . . . . 16.6 100 71 84.7 179 May 5-7 . . . . . . . . . . . . .. ay 19-23 . . . . . . . . . .. 15.3 100 71 84.2 180 May 5-6 . . . . . . . . . . . . .. May 19-23 14.8 100 71 84.2 181 May 5-7 . . . . . . . . . . . . . . May 19-23 . . . . . . . . . .. 14.6 100 71 84.2 182 May 7-10 . . . . . . . . . . . . . May 20-29 13.1 100 71 84.6 183 May -10 . . . . . . . . . . . . May 20-26 . . . . . . . . . . . 14.4 100 71 85.2 184 May 10-15 . . . . . . . . . . . . . May 22-27 13.5 100 71 85.6 185 May 11-14 . . . . . . . . . . . . . May 20-26 . . . . . . . . . . . 12.6 100 75 86.5 186 May 12-14 . May 22-26 12.8 100 75 87.0 187. May 12-15 . . . . . . . . . . . . . May 22-2 . . . . . . . . . . . 12.8 100 75 86.8 188 May 14-17 . . . . . . . . . . . . . May 24-28 . . . . . . . . . . . 11 .2 100 76 87.0 189 May 15-17 . . . . . . . . . . . .. May 27-31 . . . . . . . . . .. 13.8 100 76 86.3 190 May 16-17 . . . . . . . . . . . . . May 28-31 . . . . . . . . . . . 13 100 76 86.0 191 May 16-17 . . . . . . . . . . . .. May 26-30 . . . . . . . . . . 12.5 100 76 86.9 192 May 16-17 . . . . . . . . . . . . . Ma 26-29. . . . l1 .3 100 76 86 .3 193 May 17-21 . . . . . . . . . . . .. May 31-June 3 . . . . . . . 13.3 98 76 85.5 *Incomp1ete record. *Incomplete record. THE SWEET POTATO WEEVIL. 3'2’ Table 9—Duration of Pupal Stage—-Continued Avera e Temperature Lot Pupated Emerged perio , _ N0. days Max. Mm. Mean 1919 1919 194 May 19-20 . . . . . . . . . . . .. May 31-June 2 . . . . . . . 13.5 94 76 85.3 195 May 20-21 . . . . . . . . . . . .. June 2-6 . . . . . . . . . . .. 13.8 96 76 84.5 196 May 19-21 . . . . . . . . . . . .. June l4 . . . . . . . . . . .. 13.3 94 76 84.9 197 Vlay 21-24 . . . . . . . . . . . . . June 2-5 . . . . . . . . . . . . 12.7 94 76 84.5 198 May 22-23 . . . . . . . . . . . .. June 1-8 . . . . . . . . . . .. 12.5 100 76 85.0 199 May 22-24 . .... . .. June 2-6 . . . . . . . . . .. 12.1 96 76 84.4 200 Vlay 23-25 . . . . . . . . . . . . . June 4-9 . . . . . . . . . . .. 13.1 101 76 85.5 201 Vlay 24-25 . . . . . . . . . . . . . June 4-7 . . . . . . . . . . .. 13.7 96 76 84.3 202 Vlay 24-25 . . . . . . . . . . . . . June 8-10 . . . . . . . . . . . 14.3 101 76 85.5 203 Vlay 25-26 . . . . . . . . . . . .. June 6-10 . . . . . . . . . . . 13.7 101 76 85.6 204 .VIay 26-27 . . . . . . . . . . . . . June 7-10 . . . . . . . . . . . 13.3 101 76 85.7 205 May 27 . . . . . . . . . . . . . . . June 9-10. . 13.8 101 76 85.8 206 May 27-28 . . . . . . . . . . . .. June 10-11........... 13.5 101 76 85.6 207 May 28 . . . . . . . . . . . . . .. June 10-11........... 13.7 101 76 85.5- 208 May 28-29 . . . . . . . . . . . . . June 11-12 . . . . . . . . . . . 13 ._8 101 76 85.8 209 Vlay 29-31 . . . . . . . . . . . . . June 9-12 . . . . . . . . . . . 11.6 101 76 85.8 210 June 1 . . . . . . . . . . . . . .. June 14-15 . . . . . . . . . .. 13.8 101 76 86.8 211 June 3-5 . . . . . . . . . . . . .. June 13-18 . . . . . . . . . .. 12 101 76 86.8 212 June 3-4 . . . . . . . . . . . . .. June 13 1 12.7 101 76 87.3 213 June 4-5 . . . . . . . . . . . . . . June 16-18 . . . . . . . . . . . 12 101 76 87.3 214 June 5 . . . . . . . . . . . . . .. June 14-16 . . . . . . . . .. 11 .4 101 76 88.0 215 June 4-5 . . . . . . . . . . . . .. June 13-19 . . . . . . . . .. 12.4 101 76 87.5- 216 June 5-6 . . . . . . . . . . . . .. June 15-25 . . . . . . . . . .. 13.4 101 76 88.1 217 June 7 . . . . . . . . . . . . . .. June 16-22 . . . . . . . . . .. 12 101 76 88.7 218 June 8 . . . . . . . . . . . . . .. June 16-20 . . . . . . . . . .. 11.3 101 76 88.5 219 June 9 . . . . . . . . . . . . . .. June 20-22.... 11.2 96 76 88.0 220 June 9-10 . . . . . . . . . . . .. June 19-22. . . . 11 .6 96 76 88.0" 221 June 10-11 . . . . . . . . . . . .. June 21-23........... 11.8 96 76 87.8 222 June 10-11 . . . . . . . . . . . . . June 21-24 . . . . . . . . . . . 12 96 76 87.9 223 June 11 . . . . . . . . . . . . . . . June 22-25 . . . . . . . . . . . 12.1 96 80 88.3 224 June 11-12 . . . . . . . . . . . .. June 21-28. . .. . . . . . .. 12.2 96 8O 88.3’ 225 June 12 . . . . . . . . . . . . . .. June 22-25........... 11.5 95 80 88.2 226 June 14-15 . . . . . . . . . . . . . June 23-28 . . . . . . . . . . . 10.7 94 80 88.0 227 June 15 . . . . . . . . . . . . . .. June 25-30.... 12.2 95 80 88.4 228 June 16-17 . . . . . . . . . . . .. June 25-27. . . 11.6 94 81 88.5 229 June 16-17 . . . . . . . . . . . .. June 27-30 . . . . . . . . . .. 10.2 95 81 88.8 230 June 17-18 . . . . . . . . . . . .. June 25-30 . . . . . . . . . .. 10.1 95 81 88.9 ‘231 June 18-22 . . . . . . . . . . . .. June 26-30 . . . . . . . . . . 9.5 95 81 88.9 232 June 19-21 . . . . . . . . . . . . . June 28-July 1 . . . . . . . 10.1 96 81 89.1 233 June 20-22 . . . . . . . . . . . . . June 28-July 5 . . . . . . . 10 97 81 90.0 234 June 21-22 . . . . . . . . . . . .. June 27-July 3 . . . . . .. 9.6 96 81 89.9 235 June 22-23 . . . . . . . . . . . . . June 30-July 6 . . . . . . . 10.8 97 83 91 .0 236 June 21-24 . . . . . . . . . . . . . June 30-July 1 . . . . . . . 9.4 96 81 89.0 237 June 24 . . . . . . . . . . . . . .. July 1-5 . . . . . . . . . . .. 8.2 97 84 91 .3 238 Iune 25-26 . . . . . . . . . . . . . July 1-5 . . . . . . . . . . . . 7.7 97 84 91 .6 239 June 26-27 . . . . . . . . . . . . . July 4-6 . . . . . . . . . . . . 8.8 97 84 92.1 240 June 27 . . . . . . . . . . . . . . . July 3-7 . . . . . . . . . . . . 8 .4 97 84 92.5 241 June 28-29 . . . . . . . . . . . . . July 3-6 . . . . . . . . . . . . 7.7 97 87 93.0 242 June 29-30 . . . . . . . . . . . . . July 6-7 . . . . . . . . . . . . 8.2 97 88 93.3 243 June 29-30 . . . . . . . . . . . . . July 8-9 . . . . . . . . . . . . 8.7 97 85 93. 1 244 June 29 . . . . . . . . . . . . . . . July 6-12 . . . . . . . . . . . 9.4 100 85 93.6 245 June 30-July 1 . . . . . . . . . July 7-14 . . . . . . . . . . . 8.7 100 85 94.5 246 July 1 . . . . . . . . . . . . . . . . July 9-12 . . . . . . . . . . . 9 100 85 93.9 247 July 2 . . . . . . . . . . . . . . .. July 10-13 . . . . . . . . . . . 9.3 100 85 94.3 248 July 3 . . . . . . . . . . . . . . . . July 12-13 . . . . . . . . . . . 9.5 100 85 94.3 249 July 6-7 . . . . . . . . . . . . .. July 13-18 . . . . . . . . . . . 9.1 101 85 94.8 250 July 7 . . . . . . . . . . . . . . .. July 14-1 . . . . . . . . . .. 8.8 101 85 94.7 251 July 7-8 . . . . . . . . . . . . .. July 12-15 . . . . . . . . . .. 7.3 100 85 95.0 252 luly 9 . . . . . . . . . . . . . . . . uly 16- . . . . . . . . . . . 8.6 101 87 95.2 253 July . . . . . . . . . . . . . . . uly 15- . . . . . . . . . . . 8 101 87 95.2 254 July . . . . . . . . . . . . . July 16-19 . . . . . . . . . .. 7.8 101 87 95.2 255 July 10 . . . . . . . . . . . . . . .. July 16-19 . . . . . . . . . . . 8.1 101 87 95.4 256 July 10-11 . . . . . . . . . . . . . July 18-2 . . . . . . . . . . . 8 101 87 95.2 257 ly 11 . . . . . . . . . . . . . . .. July 17-21 . . . . . . . . . .. 8,1 101 87 95.2 258 July 11-12 . . . . . . . . . . . . . July 17-21 . . . . . . . . . . . 7.6 101 87 95.2 *259 July 12-13 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 260 July 13-14 . . . . . . . . . . . . . July 19-24 . . . . . . . . . . . 7.6 101 86 93.5 261 July 14-16 . . . . . . . . . . . . . July 20-26 . . . . . . . . . . . 9.3 ' 101 86 92.8 262 July 16 . . . . . . . . . . . . . . . . July 25- . . . . . . . . . . . 10.2 101 85 92.4 263' July 17._ . . . . . . . .. . . .1 .. July 25-27 . . . . . . . . . .. 9.9 97 86 92.3 264 July 18-19 . . . . . .3 . . . . . . . July 27-28 . . . . . . . . . . . 9.6 97 85 91 .9 265 Iuly 19 . . . . . . . . . . . . . . . . July 26-Aug 2 . . . . . . . 9.7 98 85 92.8 266 uly 19.. . . . . . . . . . . . . .. Jul 28-31 . . . . . . . . . .. 10.2 98 85v 92.5 267 Iuly 19-20 . . . . . . . . . . . . . July 28-Aug 2 . . . . . . . 10.8 98 85 9218 268 July 21 . . . . . . . . . . . . . . .. July 31-Aug 1 . . . . . .. 11 .4 98 85 92.4 269 July 22 . . . . . . . . . . . . . . . . ug. 1- . . . . . . . . . . . . 11.2 98 85 92,6 270 July 22-23 . . . . . . . . . . . . . Aug. 2-4 11 .3 98 85_ 92. 271 July 23-24 . . . . . . . . . . . . . Aug. 3-5 . . . . . . . . . . . . . 10.6 98 85 93.2 *Incomplete record. 38 BULLETIN N0. 308. Table 9—--Duration of Pupal Stage—-C0ntinued Ave_ra e Temperature Lot Pupated Emerged peno , _ N0. days Max. Mm. Mean 272 July 24-25 . . . . . . . . . . . . . Aug. 4-6 . . . . . . . . . . . . 10.5 98 85 93.4 273 July 27-28 . . . . . . . . . . . . . Aug. 4-6 . . . . . . . . . . . . 9 98 85 93.7 274 July 28-29 . . . . . . . . . . . . . Aug. 5-6 . . . . . . . . . . . . 8. 98 90 94.1 275 July 30 . . . . . . . . . . . . . . . . Aug. 7-10. 9 98 90 93.9 276 July 30-Aug. 3 . . . . . . . . . Aug. 7-11 . . . . . . . . . . . 8. 98 90 94.0 Aug. 1 . . . . . . . . . . . . . . . Aug 11 . . . . . . . . . . . . . 1O 98 90 93.8 279 Aug. 1 . . . . . . . . . . . . . . . . Aug 9-14 . . . . . . . . . . . 10.4 98 88 93.1 Aug. 2-3 . . . . . . . . . . . . . . . Aug 12-13 . . . . . . . . . . . 11 .5 98 88 93.1 282 Aug. 3-5 . . . . . . . . . . . .. Aug 12-14 . . . . . . . . . .. 9 98 88 93.0 *283 Aug. 6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 284 Aug. 7 . . . . . . . . . . . . . . . Aug. 16 . . . . . . . . . . . . . 9 98 88 92.5 285 Aug. 8 . . . . . . . . . . . . . . . Aug. 16-17 9.2 98 88 92.3 286 Aug. 8-9 . . . . . . . . . . . . . . Aug. 17-18 . . . . . . . . . . . 9.6 98 88 92.3 287 Aug. 10 . . . . . . . . . . . . . . . Aug. 18-19 . . . . . . . . . . 8.8 95 85 92.0 288 Aug. 11 . . . . . . . . . . . . . . . Aug. 18-20 . . . . . . . . . . . 8.9 95 85 91 .3 289 Aug. 11 . . . . . . . . . . . . . . . Aug. 19-25 . . . . . . . . . . 10 95 81 89.5 290 Aug. 12 . . . . . . . . . . . . . . . Aug 18-27. . 10.8 95 80 88.9 291 Aug. 12-13 . . . . . . . . . . . . . Aug 23-26. 12.3 95 80 89.0 292 Aug. 13-14 . . . . . . . . . . . . . Aug 26-27 . . . . . . . . . .. 13.6 95 80 88.7 293 Aug. 10-14 . . . . . . . . . . . . . Aug 1-28 . . . . . . . . . . . 11.7 95 80 89.2 294 Aug. 1 . . . . . . . . . . . . . . . Aug. . . . . . . . . . . . . . 12 95 80 88.7 295 Aug. 15-16 . . . . . . . . . . . . . Aug. 25-28 11 .2 95 8O 88.2 296 Aug. 16-17 . . . . . . . . . . . . . Aug. 28-29 11 .5 95 80 88.0 297 Aug. 18 . . . . . . . . . . . . . . . Aug. 27-29 10.8 95 80 87.2 298 Aug. 19 . . . . . . . . . . . . . . . Aug. 28-29 . . . . . . . . . . . 10.5 93 80 86.9 299 Aug. 19-20 . . . . . . . . . . . . . Aug. 26-Sept 5 . . . . . . 11.7 95 77 85.6 300 Aug. 20-21 . . . . . . . . . . . . . Aug. 29-Sept 3 . . . . . . 11 .8 95 77 87.0 301 Aug. 21 . . . . . . . . . . . . . . . Sept. 4-8 . . . . . . . . . . . 15.4 95 77 86.1 302 Aug. 22 . . . . . . . . . . . . . . . Sept. 3-8 . . . . . . . . . . . 14.5 95 77 86.1 303 Aug. 23 . . . . . . . . . . . . . . . Sept. 4-9 . . . . . . . . . . . 15.2 95 77 86.3 304 Aug. 25 . . . . . . . . . . . . . . . Sept 8 . . . . . . . . . . . . . 14 95 77 86.2 305 Aug. 26 . . . . . . . . . . . . . . . Sept. 8-9 . . . . . . . . . . . 13.6 95 77 86.4 306 Aug. 26-27 . . . . . . . . . . . . . Sept. 8-9 . . . . . . . . . . . 13.3 95 77 86.4 307 Aug 27-28 . . . . . . . . . . . . . Sept. 6-10 . . . . . . . . .. 12.3 95 77 86.7 308 Aug 28-29 . . . . . . . . . . . . . Sept. 10-12 . . . . . . . . . . 13 96 77 87.2 309 Aug 29-30 . . . . . . . . . . . . . Sept. . . . . . . . . . . . . . 13 95 77 86.7 310 Aug 1 . . . . . . . . . . . . . . . Sept. 12-13 . . . . . . . . . . 12.5 97 77 86.5 311 Sept 2-3 . . . . . . . . . . . .. Sept. 13-16 . . . . . . . . . . 12.3 97 77 86.0 312 Sept . . . . . . . . . . . . . . . Sept. 14-15 . . . . . . . . . . 12.5 97 77 86.1 313 Sept 2-3 . . . . . . . . . . . .. Sept. 5-17 . . . . . . . . .. 13.3 97 77 85.9 314 Sept 3 . . . . . . . . . . . . . . . Sept. 17-18 . . . . . . . . . . 14.8 97 77 86.2 315 Sept 4-6 . . . . . . . . . . . .. Sept. 8-19 . . . . . . . . .. 15.2 97 77 86.5 316 Sept 5 . . . . . . . . . . . . . . . Sept. 22-25 . . . . . . . . . . 17.9 97 74 85 .6 317 Sept 6 . . . . . . . . . . . . . . . Sept. 23-29 . . . . . . . . . . 20.7 97 74 85.1 318 Sept 8-9 . . . . . . . . . . . . . Sept. 23-25 . . . . . . . . . . 16.4 97 74 86.0 319 Sept 11-12 . . . . . . . . . . . . Sept. 24-27 . . . . . . . . . . 12.8 97 74 84.4 320 Sept 13-15 . . . . . . . . . . . . Sept. 25-28 . . . . . . . . . . 12.3 92 74 83.7 321 Sept. 16 . . . . . . . . . . . . . . . Sept. 9 . . . . . . . . . . . . . 13 96 74 82. 1 322 Sept 16-18 . . . . . . . . . . . . Sept. 28-29 . . . . . . . . . . 12.2 96 74 82.1 323 Sept 17 . . . . . . . . . . . . . . . Sept. 29-Oct 1 . . . . . . . 13.3 96 74 84.1 324 Sept 18 . . . . . . . . . . . . . .. Oct. 1-3 . . . . . . . . . . .. 14.3 96 74 84.3 325 Sept 19 . . . . . . . . . . . . . .. Oct. -3 . . . . . . . . . . . . 13 96 74 84.1 326 Sept 0 . . . . . . . . . . . . . .. Oct. 4-8 . . . . . . . . . . . . 15.6 96 74 84.4 *327 Sept 20-21 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ~ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 328 Sept 21-22 . . . . . . . . . . . . Oct 3-7 . . . . . . . . . . . . 13.7 96 74 84.1 329 Sept . . . . . . . . . . . . . . . Oct 4-7 . . . . . . . . . . . . 13.5 96 74 83.8 330 Sept 22-23 . . . . . . . . . . .. Oct 8-11 . . . . . . . . . .. 17 96 74 84.3 331 Sept 3 . . . . . . . . . . . . . . . Oct. 9-13 . . . . . . . . . .. 18 96 74 83.7 332 Sept . . . . . . . . . . . . . . . Oct. 12-13 . . . . . . . . . . . 18.6 96 74 84.1 333 Sept 24-28 . . . . . . . . . . . . Oct. 10-18 . . . . . . . . . . . 18.5 96 69 82.3 334 Sept 26-27 . . . . . . . . . . . . Oct. 11-18 . . . . . . . . . . . 17.5 96 69 82.7 335 Sept 27-28 . . . . . . . . . . . . Oct. 12-19 . . . . . . . . . . . 16.6 96 69 82.4 336 Sept . . . . . . . . . . . . . . . Oct. 13-18 . . . . . . . . . . . 15 94 69 82.2 337 Oct . . . . . . . . . . . . . . Oct. 18-20 . . . . . . . . . . . 15.5 93 69 80.3 338 Sept 30-Oct 6 . . . . . . . . . Oct. 17-28 . . . . . . . . . . . 13 94 69 82.3 339 Oct 6-10 . . . . . . . . . . . . . Oct 22-25 . . . . . . . . . . . 15.7 91 69 80.2 340 Oct 8-10 . . . . . . . . . . . .. Oct 23-27 . . . . . . . . . . . 15.6 91 69 80.4 *341 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . *342 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 343 Oct . . . . . . . . . . . . . . . . Oct. 23-27 . . . . . . . . . . . 15.8 91 69 80.4 344 Oct 10-14 . . . . . . . . . . . . . Oct. 25-28 . . . . . . . . . . . 15.6 90 69 79.9 345 Oct 8-15 . . . . . . . . . . . . . Oct. 5-28 . . . . . . . . . . . 15.1 91 69 80.7 346 Oct 15-16 . . . . . . . . . . . . . Oct. 28-Nov 3 . . . . . . . 15. 1 90 69 79.9 347 Oct 17 . . . . . . . . . . . . . . . . Oct. 27-28 . . . . . . . . . . . 13.5 90 69 81 .4 348 Oct 18 . . . . . . . . . . . . . . . . Oct 28-31 . . . . . . . . . .. 12 90 70 81.6 349 Oct 17-20 . . . . . . . . . . . . . 11 .5 90 69 83.5 THE SWEET POTATO WEEVIL. Table 9—-Durati on of Pupal Stage-—Continued 39 Aveyage Temperature L01; Pupated Emerged penod, _ Na days Max. Mm. Mean 1919 1919 350 Oct 22-23 . . . . . . . . . . . . . Oct. 29-Nov. 6 . . . . . . . 10 90 72 81.0 351 Oct 1-24 . . . . . . . . . . . . . Nov. 1- . . . . . . . . . .. 12.6 94 72 81.3 352 Oct 23-25 . . . . . . . . . . . . . Oct. 31-Nov 8 . . . . . . . 12. 1 90 72 80.7 353 Oct. 24-25 . . . . . . . . . . . . . Nov. 3- . . . . . . . . . . . 13.2 90 72 80.2 354 Oct. 5 . . . . . . . . . . . . . . .. Nov. 6-9 . . . . . . . . . .. 14 94 72 80.2 355 Oct. 6 . . . . . . . . . . . . . . .. Nov 3-10 . . . . . . . . .. 13.7 94 72 80.2 356 Oct. 26-28 . . . . . . . . . . . . . Nov 6-14 . . . . . . . . . . 15.3 94 66 79.6 357 Oct. 27-30 . . . . . . . . . . . . . Nov 9-17 . . . . . . . . . . 16.7 94 66 79.1 358 Oct. 29-31 . . . . . . . . . . . . . Nov 9-16 . . . . . . . . . . 14. 1 94 66 79.4 359 Oct. 30-31 . . . . . . . . . . . . . Nov 15-16 . . . . . . . . . . 15.7 94 66 79.0 360 Oct 31-Nov 3 . . . . . . . .. Nov 14-16 . . . . . . . . .. 14 94 66 79.0 361 Oct 31-Nov 1 . . . . . . . .. Nov 16-21 . . . . . . . . .. 14.5 94 66 78.9 362 Nov 1-3 . . . . . . . . . . . . . Nov 17-23 . . . . . . . . . . 14.8 94 66 79.1 363 Nov 5-8 . . . . . . . . . . . .. Nov 15-26 . . . . . . . . .. 13.4 94 66 80.7 364 Nov 7-8 . . . . . . . . . . . .. Nov 20-23 . . . . . . . . .. 13.7 94 66 80.0 365 Nov 9-10 . . . . . . . . . . .. Nov 22-29 . . . . . . . . .. 13.5 94 66 79.5 366 Nov 10-11 . . . . . . . . . . .. Nov 20-28 . . . . . . . . .. 14.2 89 66 79.9 367 Nov 11. . . . . . . . . . . . . .. Nov 20-30 . . . . . . . . .. 13.7 89 66 78.7 368 Nov 12 . . . . . . . . . . . . . .. Nov 24-27 . . . . . . . . .. 13.8 89 66 79.9 369 Nov 13-14 . . . . . . . . . . .. Nov 25-Dec. . . . . . .. 14.4 89 64 77.4 370 Nov 13-15 . . . . . . . . . . .. Nov 27-‘Dec. 1 14.9 89 64 78.2 371 Nov 14-15 . . . . . . . . . . . . Nov 28-Dec. 3 . . . . . . . 15.3 89 64 77.6 372 Nov 16 . . . . . . . . . . . . . .. Nov 26-Dec. 5 14.5 89 64 77.1 373 Nov 17 . . . . . . . . . . . . . . . Nov 28-Dec. 9 16 94 64 78.1 374 Nov 18 . . . . . . . . . . . . . .. Dec 1-8 . . . . . . . . . . .. 16.5 94 64 77.8 375 Nov 18 . . . . . . . . . . . . . .. Dec 3-8 . . . . . . . . . . .. 19.2 94 64 77.8 376 Nov 18-19 . . . . . . . . . . .. Dec 5-9 . . . . . . . . . . .. 17.8 94 64 78.1 377 Nov 19 . . . . . . . . . . . . . .. Dec 1-8 . . . . . . . . . . .. 16.6 94 64 77.7 378 Nov 20 . . . . . . . . . . . . . .. Dec 5-11 . . . . . . . . . .. 18.1 94 64 77.6 379 Nov 20-21 . . . . . . . . . . .. Dec 8-11 . . . . . . . . . .. 19 94 64 77.6 380 Nov 1 . . . . . . . . . . . . . .. Dec 8-13 . . . . . . . . . .. 18.2 94 60 77.3 381 Nov 21-22 . . . . . . . . . . .. Dec 9-14 . . . . . . . . . .. 19.5 94 60 77.0 Nov 4 . . . . . . . . . . . . . .. Dec 12-16 . . . . . . . . . .. 19.5 94 60 75.3 384 Nov. 25 . . . . . . . . . . . . . .. Dec 11-15 . . . . . . . . . .. 18.7 94 60 75.1 385 Nov 26-Dec 3 . Dec 14-27 . . . . . . . . . .. 22.8 94 56 75.5 386 Nov 28-30 . . . . . . . . . . .. Dec 13-26 . . . . . . . . . .. 22.8 94 56 76.0 387 Dec 1-4 . . . . . . . . . . . . .. Dec 20-27 . . . . . . . . . .. 19.5 94 56 76.4 388 Dec 4 . . . . . . . . . . . . . . . Dec. 22-31 . . . . . . . . . . . 19.7 94 56 77.8 389 Dec 5 . . . . . . . . . . . . . . . Dec. 20-30 . . . . . . . . . . . 20.7 94 56 77.8 390 Dec 6 . . . . . . . . . . . . . . . Dec. 23-Jan. 4, 1920. . 22.4 94 56 78.1 391 Dec 6 . . . . . . . . . . . . . . . Dec. 26-Jan. 4, 1920. . 24.1 94 56 78.1 392 Dec 8 . . . . . . . . . . . . . . . Dec. 31-J1a61é04, 1920. . 25.6 93 56 77.6 393 Dec 8 . . . . . . . . . . . . . . . Jan. -7 . . . . . . . . . . .. 26.8 93 56 77.3 394 Dec 9 . . . . . . . . . . . . . .. Dec 30-Jan 12 . . . . .. 26.6 93 56 77.2 395 Dec 10 . . . . . . . . . . . . . .. Jan 1-8 . . . . . . . . . . . . 26.4 93 56 77.2 396 Dec 11 . . . . . . . . . . . . . .. Jan 4-7 . . . . . . . . . . . . 26.6 93 56 77.3 397 Dec 12 . . . . . . . . . . . . . .. Jan 7-9 . . . . . . . . . . . . 26.3 93 56 77.1 398 Dec 13 . . . . . . . . . . . . . .. Jan 6-17 . . . . . . . . . .. 27.8 96 56 78.4 399 Dec 18 . . . . . . . . . . . . . . . Jan 6-14 . . . . . . . . . . . 23 93 56 81 .7 400 Der 19 . . . . . . . . . . . . . . . Jan 7-15 . . . . . . . . . . . 24 93 56 81.3 401 Dec. 2O . . . . . . . . . . . . . .. Jan 13-17 . . . . . . . . . .. 25.2 96 56 81.5 402 Dec. 22 . . . . . . . . . . . . . . . Jan 14-17 . . . . . . . . . . . 24.7 9.6 56 82.1 403 Dec. 23 . . . . . . . . . . . . . . . Jan 15-22 . . . . . . . . . . . 26 96 56 79.7 *404 Dec 24 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 405 Dec. 24-25 . . . . . . . . . . . . . Jan. 14-25 . . . . . . . . . . . 25.3 96 56 79.4 406 Dec. 25 . . . . . . . . . . . . . . . Jan. 14-23 . . . . . . . . . . . 22. 96 56 79.8 407 Dec. 26-27 Jan. 17-19 . . . . . . . . . . . 22 96 71 80.3 408 Dec. 27 . . . . . . . . . . . . . . . Jan 17 . . . . . . . . . . . . . . 21 96 71 80.0 409 Dec. 29 . . . . . . . . . . . . . .. Jan 18-19 . . . . . . . . . .. 20.7 96 71 80.5 410 Dec. 3O . . . . . . . . . . . . . .. Jan 17-23 . . . . . . . . . .. 21.1 96 70 80.5 411 Dec 31. . i920 . . . . . . . .. Jan 19-23 . . . . . . . . . .. 21.5 96 70 80.8 412 Jan 1 . . . . . . . . . . . . . . . . Jan 20-26 . . . . . . . . . . . 22.7 96 70 83.0 413 Jan 2 . . . . . . . , . . . . . . . . Jan 21-26 . . . . . . . . . .. 22.2 96 70 83.2 414 Jan 3 . . . . . . . . . . . . . . . . Jan 22-26 . . . . . . . . . .. 21.7 96 80 83.5 415 Jan 4 . . . . . . . . . . . . . . . . Jan 23-27 . . . . . . . . . .. 21.3 96 70 83.5 416 Jan 4-5 . . . . . . . . . . . . . . Jan 23-28 . . . . . . . . . . . 20.4 96 70 83.2 417 Jan 5-6 . . . . . . . . . . . . .. Jan 23-31 . . . . . . . . . .. 19.6 96 64 79.3 418 Jan 6 . . . . . . . . . . . . . . . . Jan 23-Feb 1 . . . . . .. 18.8 96 64 79.9 419 Jan 7 . . . . . . . . . . . . . . . . Jan 23-Feb 7 . . . . . .. 22.2 96 64 80.3 420 Jan 7-8 . . . . . . . . . . . . .. Jan 23-Feb 1 . . . . . .. 18 96 64 80.0 421 Jan. . . . . . . . . . . . . . . .. Jan 27-Feb 3 . . . . . . . 22.3 96 64 80.3 422 Jan. 9-10 . . . . . . . . . . . .. Jan 24-Fcb 5 . . . . . .. 21 96 64 80.6 423 Jan. 10-11 . . . . . . . . . . . .. Jan 24-31 . . . . . . . . . .. 19.7 96 64 80.3 424 Jan. 11-12 . . . . . . . . . . . . . Jan 24-30 . . . . . . . . . . . 18 96 64 80.3 425 Jan. 13 . . . . . . . . . . . . . . . . Jan 27-Feb 4 . . . . . . . 18.8 96 64 80.9 *1 ncomplete record. “incomplete record. 40 BULLETIN N0. 308. Table 9—-Duration of Pupal Stage-{Zontinued Avera e Temperature Lot Pupated Emerged perio , No. days Max. Min. Mean 1920 1920 426 Jan. 14-15 . . . . . . . . . . . . . Jan. 30-Feb. 5 . . . . . . . . 17.4 96 64 80.8 427 Jan; 16 . . . . . . . . . . . . . . .. Feb. 2-6 . . . . . . . . . . .. 19.5 96 64 . 80.4 428 Jan. 17 . . . . . . . . . . . . . . . . Feb. 6-7 . . . . . . . . . . . . 20.5 95 64 80.2 429 Jan. Feb. 5-9 . . . . . . . . . . . . 18.8 95 64 . 79.5 430 Jan. 2 Feb. 2-7 . . . . . . . . . . . . 16 95 64 79. 1 431 Jan. 21 . . . . . . . . . . . . . . . . Feb. 4-6 . . . . . . . . . . .. 14.7 - 95 64 78.5 432 Jan.[22-23 . . . . . . . . . . . . . Feb. 4-7 . . . . . . . . . . .. 15.2 95 64 . 78.8 _433 Jan. 24 . . . . . . . . . . . . . . . . Feb. 7 . . . . . . . . . . . . . 14 95 64 79.0 434 Jan. 26 . . . . . . . . . . . . . . .. Feb. 9-11 . . . . . . . . . .. 14.6 95 64 . 78.9 435 Jan. 27. . .- . . . . . . . . . . . .. Feb. 6-11 . . . . . . . . . .. 13.2 95 64 79. 1 436 Jan. 27-28 . . . . . . . . . . . . . Feb. 7-11 . . . . . . . . . . . 12.8 95 64 79.1 -437 Jan. 28 . . . . . . . . . . . . . . . . Feb. 9-11 . . . . . . . . . . . 12.5 95 64 79.3 438 Jan. 29 . . . . . . . . . . . . . . . . Feb 9-13 . . . . . . . . . . . 12 95 64 79.1 439 Jan. 30 . . . . . . . . . . . . . . .. Feb 11-15 . . . . . . . . . .. 12.5 95 66 78.8 440 Jan. 30 . . . . . . . . . . . . . . . . Feb 12-22 . . . . . . . . . . . 17.8 95 58 77.5 441 Feb. 2 . . . . . . . . . . . . . . .. Feb 11-25 . . . . . . . . . .. 17.7 95 58 77.0 442 Feb. 3 . . . . . . . . . . . . . .. Feb 17-27 . . . . . . . . . .. 18.8 9O 58 76.2 443 Feb. 5 . . . . . . . . . . . . . .. Feb 21-26 . . . . . . . . . .. 18.5 90 58 76.1 444 Feb. 6 . . . . . . . . . . . . . . . Feb 22-25 . . . . . . . . . . . 17.1 88 58 75.9 445 Feb. 7 . . . . . . . . . . . . . . . . Feb 22-24 . . . . . . . . . . . 15.8 88 58 75.4 446 Feb. 9 . . . . . . . . . . . . . . . Feb. 24-27 . . . . . . . . . . . 16.1 88 58 78.8 i447 Feb 10 . . . . . . . . . . . . . . . . Feb. 25-March 1. . . 18.3 88 58 74.1 448 Feb 10-11 . . . . . . . . . . . . . March 1-2 . . . . . . . . . . 18.6 88 58 73.7 Feb 10 . . . . . . . . . . . . . . . March 1-4 . . . . . . . . . . 20.3 88 58 73.6 451 Feb 12 . . . . . . . . . . . . . .. Feb. 24-March 11 . . . . 21 .7 90 55 72.4 452 Feb 12-18 . . . . . . . . . . . . . March 5-11 . . . . . . . . . 21 90 55 72.4 453 Feb 8 . . . . . . . . . . . . . . . March 6-14 . . . . . . . . . 20.8 92 55 74. 1 454 Feb 19-20 . . . . . . . . . . . . . March 12-14 . . . . . . . . . 22.8 92 55 73.9 455 Feb 1 . . . . . . . . . . . . . . . March 14-15 . . . . . . . . . 21 .3 92 55 73.3 456 Feb . . . . . . . . . . . . . . . . March 15-18 . . . . . . . . . 22.6 92 55 74.6 457 Feb 22-23 . . . . . . . . . . . . . March 13-19 . . . . . . . . . 21.5 92 55 75.0 458 Feb 23 . . . . . . . . . . . . . . . March 15-19 . . . . . . . . . 22.8 92 55 74.8 459 Feb. 26 . . . . . . . . . . . . . . . . March 18-26 . . . . . . . . . 22.4 92 55 76.1 460 Feb. 26 . . . . . . . . . . . . . . . . March 19-26 . . . . . . . . . 23.1 92 55 76. 1 461 Feb. 27 . . . . . . . . . . . . . . . . March 21-26 . . . . . . . . . 24.8 92 55 76.3 462 Feb. 28 . . . . . . . . . . . . . . . March 21-28 . . . . . . . . . 25 .2 92 55 76.8 463 March 1 . . . . . . . . . . . . . March 25-27 . . . . . . . . . 25.8 92 55 77.4 464 March 2 . . . . . . . . . . . . . . March 27-30. ._ . . . . . . . 25.3 92 55 77.8 465 March 4 . . . . . . . . . . . . . March 29-April1. . . 26.5 92 55 78.2 466 March 6 . . . . . . . . . . . . . March 31-April 3. . . . . 26.8 92 55 79.0 467 March 7 . . . . . . . . . . . . . . March 31-April 3. . . . . 25.9 92 55 79.6 468 March 8 . . . . . . . . . . . . . . March 31-Apr1l 2. . . . . 25.1 92 62 80.6 469 March 10 . . . . . . . . . . . . . . April 1-4 . . . . . . . . . . . 24.3 92 73 80.6 470 ‘Vlarch 12 . . . . . . . . . . . . . . April 3-5 . . . . . . . . . . . 23.1 92 68 79.9‘ 471 March 13 . . . . . . . . . . . . . . April 5-7 . . . . . . . . . . . 23.7 92 68 79.4 472 March 14 . . . . . . . . . . . . .. April 7-9 . . . . . . . . . . . 25 87 68 79.3 473 March 14-15 . . . . . . . . . . . April 5-11 . . . . . . . . . . 24.8 87 68 79.5 474 March 15 . . . . . . . . . . . . . . April 5-12 . . . . . . . . . . 25 87 68 79.6 475 March 14-18 . . . . . . . . . . . April 7-14 . . . . . . . . . . 23.7 87 68 79.4 476 March 18-19 . . . . . . . . . . . April -15 . . . . . . . . . . 24.4 87 68 79.1 477 March 20 . . . . . . . . . . . . . April 13-14 . . . . . . . . . . 24.2 87 68 78.8 478 March 21-22 . . . . . . . . . . . April 14-17 . . . . . . . . . . 22.4 94 68 79.2 479 arch 22 . . . . . . . . . . . . . . April 14-17 . . . . . . . . . . 21 .6 94 68 79.3 480 March 23-24 . . . . . . . . . . . April 15-18 . . . . . . . . . . 21 .3 94 68 79.6 481 March 25-26 . . . . . . . . . . . April 17-18 . . . . . . . . . . 22.1 94 68 79.5 482 March 27-28 . . . . . . . . . . . April 17-20 . . . . . . . . . . 21 94 68 79.7 483 March 28 . . . . . . . . . . . . . . April 18 . . . . . . . . . . . . . 21 94 68 79.2 484 March 29 . . . . . . . . . . . . . April 18-19 . . . . . . . . . . 19.8 94 68 79.5 485 March 30 . . . . . . . . . . . . . April 18-19 . . . . . . . . . . 19.2 94 68 79.7 486 Mar ' 18 94 68 80.1 487 Apri ' 18 . 3 94 68 80.4 488 April 18 . 5 94 68 80 . 4 489 April 18 .6 94 68 80.9 490 April 18 . 5 94 68 81 . 4 491 April 17.4 94 71 81.9 492 April 1 7 94 73 82 . 6 493 April 17 94 73 83 .0 494 April . . . . . . . . . . . . . . . ' 17 94 73 83.1 495 April 10 . . . . . . . . . . . . . . . pril 7 . . . . . . . . . . . . . 17 94 73 82.7 April 10 . . . . . . . . . . . . . . . April 25-27 . . . . . . . . . . 16 94 73 82.7 498 April 9 . . . . . . . . . . . . . . . April 25-26 . . . . . . . . . . 16-6 94 73 83.1 499 April 10 . . . . . . . . . . . . . . . April 26-27 . . . . . . . . . . 16.6 94 73 82.7 500 April 11 . . . . . . . . . . . . . . . April 27 . . . . . . . . . . . . . 16 94 73 82. I 501 April 12 . . . . . . . . . . . . . . . April 29 . . . . . . . . . . . . . 17 94 73 82g .502 April 13 . . . . . . . . . . . . . . . April 30 . . . . . . . . . . . . . 17 94 73 82. .503 April 13 . . . . . . . . . . . . . . . April 28-May 2 . . . . . . 16.3 94 73 82.5 THE SWEET POTATO WEEVIL. Table 9—-Duration of Pupal Stage—Conti nued 41 Avera e Temperature Lot Pupated Emerged perio , _ o. - days Max. Min. Mean 1920 504 April 14 . . . . . . . . . . . . . . . April 30-May 3 . . . . . . 16.7 94 73 83. 1 505 April 1 . . . . . . . . . . . . . . . April 30-May 3 . . . . . . 16 94 73 83.3 506 April 16 . . . . . . . . . . . . . . . April 29-May 3 . . . . . . 14 .5 94 73 83.4 507 April 17 . . . . . . . . . . . . . . . May . . . . . . . . . . . . . . 15 9O 73 82.7 508 April 18 . . . . . . . . . . . . . .. May 3 . . . . . . . . . . . . .. 15 91 73 82.8 509 April 19 . . . . . . . . . . . . . . . Mav 3 14.5 94 73 82.8 510 April 22 . . . . . . . . . . . . . . . May 6-. . . . . . . . . . . . . 14 94 73 83.7 511 April 23 . . . . . . . . . . . . . .. May 7 . . . . . . . . . . . . . 14 94 73 84.0 512 April 23 . . . . . . . . . . . . . . . May 8 . . . . . . . . . . . . . 15 94 73 84.3 513 April 24 . . . . . . . . . . . . . .. May 7-8 . . . . . . . . . . . . 13.7 94 73 84.4 April . . . . . . . . . . . . . . ~ . May 8-9 . . . . . . . . . . . . 13.7 94 73 84.9 516 April 26-27 . . . . . . . . . . . . May 9-11 13 .2 94. 73 85 .5 517 April . . . . . . . . . . . . . . . May 11-12 . . . . . . . . . . 13.3 94 76 87.2 518 April 29 . . . . . . . . . . . . . .. May 11 . . . . . . . . . . . .. 12 94 79 87.8 519 April 30 . . . . . . . . . . . . . . . May 12 . . . . . . . . . . . . . 12 94 82 88.3 520 May . . . . . . . . . . . . . .. May 12 . . . . . . . . . . . .. 11 94 84 88.7 521 April 30 . . . . . . . . . . . . . .. May 11 . . . . . . . . . . . . . 11 94 82 88.3 522 May . . . . . . . . . . . . . . . May 14 . . . . . . . . . . . . . 13 94 84 87.5 523 April 30-May 1 . . . . . . . . May 16 . . . . . . . . . . . . . 16 94 80 87 .9 524 May . . . . . . . . . . . . . . May 16-20 . . . . . . . . . . 14.3 94 75 87.0- 525 May 6 . . . . . . . . . . . . . .. May 0 . . . . . . . . . . . .. 14 93 75 86.4 *Incomplete record. The existing temperatures during the period of observation were recorded by a thremograph. For each period, are given its maximum temperature and its minimum temperature. The ' mean temperature given is the average of the daily mean temperatures occurring over the eriod. In Table 10 is given the yearly variation in the duration of the pupal stage. The mean temperature does not have a definite efiect on its length. The average length of the period, for both the summer and winter months, seems to be influenced more by extreme temperatures. Table 10 Yearly Variation in ‘Duration of Pupal Stage Period, Temperature, Date days mean May, 1918 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 9.6 78.4 May, 1919 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 13.7 84.7 June, 1918 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 10.3 94.0 June, 1919 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 10.6 85.2 December, 1918 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81.6 December, 1919 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23.7 76.9 January, 1919 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 15.5 79.1 January, 1920 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17.8 79. 1 A summary containing the longest, the shortest, and the average duration of the pupal stage from May, 1918 to May, 1920, is given in Table 11. The average monthly period was obtained by totalling the daily observations and dividing by the number of collections of pupae observed during the month. During the time in which these observa- tions were made, the longest period and the shortest period averaged -18.-6 days and 1176 days, respectively. The average of the pupal stage over the entire period of observation was 15.2 days. The mean tempera- ture during this time was 83.2 degrees F. 42 BULLETIN N0. 308. Table 11 Summary of Duration of Pupal Stage Collections Month a Temperature, Longest Shortest Avera e of pupae mean period period perio observed 1918 May . . . . . . . . . . . . . . . .. 78 4 11.3 7 9.6 19 June . . . . . . . . . . . . . . . .. 94 0 13.3 7.6 10.3 30 July . . . . . . . . . . . . . . . .. 97 2 16.1 8 11.2 18 1919 January . . . . . . . . . . . . .. 79.1 17.3 10.5 15.5 13 February . . . . . . . . . . . .. 78 8 17.5 12.8 - 15.8 27 March . . . . . . . . . . . . . .. 80 4 21.1 15 18.6 29 April . . . . . . . . . . . . . . .. 82 4 19.2 13 15.8 30 May . . . . . . . . . . . . . . . .. 84 7 16.6 11.2 13.7 39 June . . . . . . . . . . . . . . . .. 85.2 13.8 7.7 10.6 36 July . . . . . . . . . . . . . . . .. 92.3 11.4 7.3 9.2 30 August . . . . . . . . . . . . . .. 90.8 15.4 8.8 11.6 31 September............ 85.1’ 20.9 12.2 15.1 25 October . . . . . . . . . . . . . . 84.5 16.7 10 14.1 23 November . . . . . . . . . . .. 79.0 22.8 13.4 16.7 24 Decemberigéb . . . . . . . . . 76.9 27.8 19.5 23.7 24 January . . . . . . . . . . . . .. 79.1 22.7 12 17.8 29 February . . . . . . . . . . . . . 76.6 25 2 15.8 20.5 21 March . . . . . . . . . . . . . .. 77.0 26.8 18 23.3 24 April . . . . . . . . . . . . . . .. 80.7 18.6 11 15.4 35 Transgform.ai'ion to Adult Shortly before transformation to the adult, the abdomen of the pupa becomes distended_ and smoother, and is more pointed on the posterior end. The elytra are now darker in color, and the proboscis is more rigid and elongated, and is pushed away from the ventral side of the thorax. Transformation begins by a series of abdominal contractions and. twisting movements, which first break the pupal skin on the dorsum of the thorax just between the base of the wings. From this point the skin splits forward over the dorsum of the prothorax and is pulied ventrally over the head and proboscis by vigorous contractions. 'l"he antennae are pulled posteriorly during this operation and are finally detached from the old skin by means of the legs. At the same time the skin is split backward on the dorsum of the abdomen from the point of the initial break, and is gradually pushed posteriorly by abdominal contractions, releasing the legs, which soon become rigid enough to assist materially in the completion of casting the pupal skin. Nor- mally the latter does not remain attached to the tip of the abdomen, but is soon pushed off completely by the legs. The Wings are exposed from beneath the elytra, and are at first wrinkled or folded. How- ever, they soon expand and extend their full length beyond the tip of the wing covers and abdomen. They are retained, in this position until sufficiently hardened, when they are folded in their normal manner and drawn under the elytra. In Figure 3 are shown newly transformed adults with the wings fully distended. The time consumed in trans- formation to adult averaged a little more than one hour. A dult Before Emergence.—-lmmediately after its transformation from the pupa the adult weevil is white, with black eyes, mandibles, and claws. The darker colorings soon begin to appear. They first become apparent onthe legs, then on the elytra, head, and beak. The change takes place THE SWEET POTATO WEEVIL. ~' 4:3 slowly and sometimes several days elapse from the beginning of the stage until the weevil has assumed its natural coloration and hardness. Before emergence the weevil is soft-bodied and comparatively helpless, being incapable of definite locomotion. If removed from the pupal cell, it totters on its legs and invariably falls upon its side or back, unable to regain an upright position. The time from transformation of the pupa to the adult, until the weevil is able to travel, is spent in the pupal cell or larval burrow’. Emergence.——The usual method of emergence from the tuber is accomplished by the weevil’s cutting a hole of sufficient size, with its mandibles, to permit its body to pass through. The emergence holes are irregular in shape and frequently several weevils leave the tuber through the same exit. This is especially true if tubers are heavily infested. At the time that the weevil leaves the tuber, it usually has assumed its natural color, but its body is still soft and does not attain its normal degree of hardness until some time after feeding has begun. Descv-ip-tion/r-The adult sweet potato weevil is a snout-beetle" with a narrow head and thorax, long legs, and a distended body, giving it an ant-like appearance, from which it very likely received its specific name, formicarius. The snout or beak slightly curved, stout, black, and about twice as long as the head. The antennae attached to the snout at about the middle or slightly beyond, reddish-brown in color, and the distal segment thickly covered with short bristly hairs; in the male this seg- ment longer, and i.n the female shorter, than all the other segments combined. Eyes black, convex, smooth and shining. Head black, fitting in the front end of the prothorax and movable like a ball and socket joint. Prothorax in front slightly wider than the head, greatly constricted behind, reddish-brown in color. The elytra wider than the head or thorax, elongate-oval in shape, very convex on the dorsum, metallic or dark-blue in. color, and folded tightly upon the body hiding completely the wings beneath them. The wings white, nearly twice as -long as the elytra ; the basal portion has several prominent dark-colored veins extending nearly to the middle. The venation on distal part of the wing much less definite and conspicuous. When in_ natural position the wing near the middle folded beneath the basal half, and again near the tip, with the latter fold directed posteriorly. The legs reddish- brown with darker markings on distal portion of the femora and tarsal joints. The claws black. The length of the weevil, including the snout extended, ranges from 5.5 mm. to 8 mm, or about one-fourth of .an inch. Views of the adult are shown in Figure 3. igu-mmztry of Development‘ All the stages of the sweet potato weevil are subject to great varia- tion, even under similar conditions, as will be noted. in the foregoing tables. In Table 12 are given the shortest and longest periods noted for the egg, larval, and pupal stages. All the shortest periods com- bined comprised but 21.8 days, and the sum of the longest periods was 77.7 days. The total number of days that comprised the shortest periods is not sufficient for the development of a single generation, 44 BULLETIN N0. 308. v 4 -,.~ -. .t 4 . t‘ ._ . d“ '..' low" ‘j 1" ,. ' t 40;‘? ""‘ ‘ L1G. “QA \ ' _. iii}; u Figure 4. _ Sweet potatoes showing injury by the sweet potato weevil: 1, tuber showing feed- mg punctures; 2, cross section of tuber showin larval tunnels; 3, infested tuber showmg larvae and pupae 1n the burrows. THE SWEET Porno WEEVIL. 45 while almost three generations were obtained during the total time con- sumed by the longest periods. Table 12 Summary of Development of Sweet Potato Weevil Egg days Larva days Pupa days Total days Shortest . . . . . . . . . . . . . . . . . . . . . . . . . . 4.8 10 7 21.8. Longest . . . . . . . . . . . . . . . . . . . . . . . . .. 14.3 35.6 27.8 77.7 Feeding H a-bits A short time after emergence the weevil begins to feed. It prefers to feed on the tuber, but when the latter is not accessible it will feed on the foliage and vines without any apparent inconvenience. The adult insect is secretive and avoids exposure by feeding on the under side of the foliage and stems near the ground. This practice of feed- ing on the plant above ground is most pronounced in the early part of the season. The larvae resulting from eggs deposited in the stems usually tunnel downward beneath the surface and may eventually reach the tubers. It is doubtful, however, if most of the tubers in the field become infested in this manner. Field observations indicate that the tubers more commonly become infested by adult weevils reaching those that are exposed by cracks in the soil, cultivation, or shallow planting. The weevil may burrow through loose soil for a short distance in order to reach the tuber. An infested vine become light green in color and assumes a “sickly” appearance, and in case of a severe infestation it dies. As a general rule, however, weevils attacking the plants above ground are not sufficiently abundant to cause a widespread destruction 0f the vines. Usually a careful. search is necessary to locate an infesta- tion and for this reason the presence of the weevil is not suspected frequently until the tubers have become badly infested. The insect in both the larva and adult stages feeds on the tubers in the field and in storage. Adults may feed in groups, although single individuals were frequently observed attacking vines and tubers. The latter are attacked usually on the under side, and at the tip or other irregular places on the surface. The feeding cavity resembles a minute pin puncture and is directed invariably straight into the tuber. Newly hatched larvae usually begin tunneling towards the center of~ the tuber, but follow no definite course, and the tunnel of a single larva may intersect itself several times. The larva always avoids eating through to the surface and exposing the burrow. As it continues to feed, the A tunnel behind it is filled with excreted and waste material. When a tub-er contains a large number of larvae the interior portion may be riddled completely, while from the outside it appears to be perfectly sound. Sometimes such infested tubers are placed in storage, where the adults emerge and continue to feed and propagate in the stored tubers. There is no discernible difference in the method of feeding of the two sexes. Location of Food Normally the adult weevil is never found far removed from its source of food supply. The ability to locate food through its own efforts is 46 BULLETIIN N0. 308. very limited, because of its restricted means of locomotion. Notwith- standing this, isolated. plants and fields of sweet potatoes are found frequently to be infested with weevils. The most plausible explanation to be offered in this connection is that the weevil is assisted to its food supply through the use of infested slips or draws. According to all the available information, this is considered the most important means by which the insect gains access to its source of food. Flightis possible, but there are no data available at this time which indicate that this method of travel in the search of food is commonly resorted to. Food within a comparatively short distance is located readily by the weevil. Tubers or remnants left in the field after the crop has been harvested, and volunteer plants, are invariably found with active weevils on them. Several instances were noted where isolated plants of I pomoea (morning-glory) were infested by the weevil. In the lab- oratory, any tubers left accessible to the weevils were attacked without much delay. There is no apparent difference in the ability of the sexes to locate food. Table 13 Length of Life of Adults Without Food. Male Female _ Period, _ v Period, No, Emerged Died days No Emerged Died days 1918 1918 1918 1918 1 Nov. 5 . . . . . . Nov. 13 . . . . . . . 8 1 ov . . . . . . . Nov . . . . . . . 8 2 Nov. 5 . . . . .. Nov. 14 . . . . . .. 9 2 Nov 1 . . . . . . . Nov 9 . . . . . .. 8 3 Nov. 5 . . . . .. Nov. 14 . . . . . .. 9 3 Nov 1 . . . . . . . Nov 12 . . . . . .. 11 4 Nov. 5 . . . . .. Nov. 16 . . . . . .. 11 4 Nov 1 . . . . . . . Nov 6 . . . . . .. 15 5 Nov. 5 . . . . .. Nov. 16 . . . . . .. 11 5 Nov 1 . . . . . . . Nov 2 . . . . . .. 11 6 Nov. 4 . . . . . . Nov. 15 . . . . . .. 11 6 Nov. 1 . . . . . . . Nov 12 . . . . . .. 11 7 Nov. 6 . . . . . . Nov. 16 . . . . . . . 10 7 Nov 7 . . . . . . . Nov. 14 . . . . . . . 7 8 Nov. 6 . . . . .. Nov. 13 . . . . . .. 7 8 Nov 8 . . . . . .. Nov 17 . . . . . .. 9 9 Nov. 6 . . . . .. Nov. 16 . . . . . .. 10 9 Nov 8 . . . . . .. Nov 13 . . . . . .. 5 10 Nov. 8 . . . . . . Nov. 14 . . . . . .. 6 10 Nov 8 . . . . . . . Nov 6 . . . . . .. 8 11 Nov. 8 . . . . .. Nov. 16 . . . . . .. 8 11 Nov 8 . . . . . .. Nov 18 . . . . . .. 1O 12 Nov. 8 . . . . .. Nov. 14 . . . . . .. 6 12 Nov 8 . . . . . . .'Nov 18 . . . . . .. 10 13 Nov. 8 . . . . .. Nov. 17 . . . . . .. 9 13 Nov 8 . . . . . .. Nov 2 . . . . . .. 1 14 Nov. 8 . . . . .. Nov. 17 . . . . . .. 9 14 Nov 8 . . . . . .. Nov 19 . . . . . .. 11 15 Nov. 8 . . . . .. Nov. 14 . . . . . .. 6 15 Nov . . . . . .. Nov 24 . . . . . .. 16 16 Nov. 8 . . . . . . Nov. l7 . . . . . .. 9 16 Nov. 16 . . . . . .. Nov 28 . . . . . .. 12 17 Nov. 16 . . . . .. Nov. 22 . . . . . .. 6 17 Nov. 16 . . . . . .. Nov 28 . . . . . .. 12 18 Nov. 16 . . . . .. Nov. 26 . . . . . .. 10 18 Nov. 16 . . . . . .. Dec 3 . . . . . .. 17 19 Nov. 16 . . . . .. Nov. 24 . . . . . .. 8 19 Nov. 16 . . . . . .. Dec. 3 . . . . . .. 17 20 Nov. 16 . . . . .. Nov. 26 . . . . . .. 10 2O Nov. 16 . . . . . .. Dec. 3. ._ . . . .. 17 21 Nov. 16 . . . . .. Nov. 26 . . . . . . . 1O 21 Nov. 16 . . . . . .. Nov. 3O . . . . . . . 14 22 Nov. 16 . . . . .. Nov. 28 . . . . . . . 12 22 Nov. 16 . . . . . . . Nov. 28 . . . . . . . 12 23 Nov. 16 . . . . . . Nov. 26 . . . . . . . 10 23 Nov. 16 . . . . . . . Nov. 28 . . . . . . . 12 24 Nov. 16 . . . . .. Nov. 28 . . . . . . . 12 24 Nov. 16 . . . . . .. Nov. 30 . . . . . .. 14 25 Nov. 16 . . . . . .[Nov. 28 . . . . . . . 12 25 Nov. 16 . . . . . . . Nov. 28 . . . . . . . 12 26 Nov. 16 . . . . .. Nov. 30 . . . . . . . 14 26 Nov. 16 . . . . . . . Nov. 22 . . . . . . . 6 27 Nov. 16 . . . . . . Nov. 28 . . . . . . . 12 27 Nov. 16 . . . . . . . Nov. 24 . . . . . . . 8 28 Nov. 16 . . . . . . Nov. 24 . . . . . . . 8 28 Nov. 16 . . . . . . . Nov. 22 . . . . . . . 6 29 Nov. 16 . . . . .. Nov. 28 . . . . . .. 12 29 Nov. 16 . . . . . .. Dec. 3 . . . . . .. 17 30 Nov. 16 . . . . .. Nov. 28 . . . . . .. 12 3O Nov. 16 . . . . . .. Nov. 28 . . . . . .. 12 31 Nov. 16 . . . . .. Nov. 28 . . . . . .. 12 31 Nov. 16 . . . . . .. Dec. 1 . . . . . .. 15 32 Nov. 16 . . . . . . Nov. 26 . . . . . . . 10 32 Nov. 16 . . . . . . . Nov. 28 . . . . . . . 12 33 Nov. 16 . . . . .. Nov. 26 . . . . . . . 1O 33 Nov. 16 . . . . . .. Nov. 3O . . . . . . . 14 34 Nov. 16 . . . . . . Nov. 26 . . . . . . . l0 34 Nov. 16 . . . . . . . Nov. 30 . . . . . . . 14 35 Nov. 16 . . . . . . Nov. 28 . . . . . . . 12 35 Nov. 16 . . . . . .. Nov. 3O . . . . . .. 14 36 Nov. 16 . . . . .. Nov. 26 . . . . . .. . 1O 36 Nov. 16 . . . . . .. Nov. 28 . . . . . .. 12 37 Nov. 16 . . . . . . Nov. 24 . . . . . . . 8 37 Nov. 16 . . . . . . . Nov. 28 . . . . . . . 12 38 Nov. 16 . . . . .. Nov. 26 . . . . . .. 10 38 Nov. 16 . . . . . .. Nov. 3O . . . . . .. 14 39 Nov. 16 . . . . .. Nov. 26 . . . . . .. 1O 39 Nov. 16 . . . . . .. Nov. 26 . . . . . .. 10 40 Nov. 16 . . . . .. Nov. 24 . . . . . .. 8 4O Nov. 16 . . . . . .. Nov. 30 . . . . . .. 14 41 Nov. 16 . . . . .. Nov. 28 . . . . . . . 12 41 Nov. 16 . . . . . .. Nov. 28 . . . . . . . 12 42 Nov._16 . . . . . . Nov. 26 . . . . . . . 1O 42 Nov. 16 . . . . . . . Nov. 28 . . . . . . . 12 43 Nov. 16 . . . . . . Nov. 26 . . . . . . . 1O 43 Nov. 16 . . . . . . . Nov. 3O . . . . . . . 14 44 Nov. 16 . . . . . . Nov. 26 . . . . . . . 10 44 Nov. 16 . . . . . . . Nov. 26 . . . . . . . 10 45 Nov. 17 . . . . . .|Nov. 28 . . . . . . . 11 45 Nov. 16 . . . . . . . Nov. 28 . . . . . . . 12 46 Nov. 17 . . . . . JNov. 26 . . . . . . . 9 46 Nov. 16 . . . . . . . Nov. 28 . . . . . . . 12 47 Nov. 17 . . . . . . Nov. 26 . . . . . . . 9 47 Nov. 16 . . . . . . . Nov. 26 . . . . . . . 1O 48 Nov. 17 . . . . . . Nov. 30 . . . . . .. 13 48 Nov. 16 . . . . . .. Nov. 26 . . . . . .. 1O THE SWEET POTATO WEEVIL. 4'7 Table 13 Length of Life of Adults Without Food-Continued Male Female Period, _ Period, No. Emerged Died days No. Emerged Died days 1918 1918 1918 1918 49 ov 17 . . . . . . Nov . . . . . . . 11 49 Nov. 16 . . . . . .. Nov. 30 . . . . . . . 14 50 Nov 17 . . . . .. Nov 28 . . . . . . . 11 50 Nov. 16 . . . . . . . Nov. 30 . . . . . .. 14 51 Nov 17 . . . . .. Nov 28 . . . . . .. 11 51 Nov. 16 . . . . . . . Nov. 28 . . . . . .. 12 52 Nov 17 . . . . .. Nov 30 . . . . . .. 13 52 Nov. 16 . . . . . . . Nov. 28 . . . . . .. 12 53 Nov 17 . . . . .. Nov 28 . . . . . . . 11 53 Nov. 16 . . . . . .. Nov. 30 . . . . . . . 14 54 Nov 17 . . . . . . Nov 28 . . . . . . . 11 54 Nov. 16 . . . . . . . Nov. 30 . . . . . . . 14 55 Nov. 17 . . . . . . Nov 26 . . . . . . . 9 55 Nov. 16 . . . . . . . Nov. 28 . . . . . . . 12 56 Nov 17 . . . . .. Nov 26 . . . . . . . 9 56 Nov. 16 . . . . . .. Nov. 28 . . . . . .. 12 57 Nov 17 . . . . . . Nov 28 . . . . . . . 11 57 Nov. 16 . . . . . . . Dec. 1 . . . . . . . . 15 58 Nov. 17 . . . . . . Nov. 28 . . . . . . . 11 58 Nov. 16 . . . . . . . Nov. 28 . . . . . . . 12 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 59 Nov.16.......Dec. 15 Length of Life of Adults Without Food During November, 1918, observations were made on 117 weevils to determine the length of life from emergence, without food, under laboratory conditions. I The results obtained from this experiment are given in Table 13. For the male sex, the minimum life period. and the maximum life period Without food were 6 and 14 days, respectively. The average life of the 58 individuals under observation was 9.9 days. The minimum period for the female sex was 6 days, the same as ob- tained for the male. The maximum life. period and the average life period, however, were longer. Four females lived for 17 days. The average life for the 59 female weevils was 12 days. From May 29, 1922, to June 11, 1922, 9'7 weevils of both sexes were isolated without food from the date of emergence. The average time that these weevils lived was about 8.1 days. The mean temperature for the period was 81.5 degrees F. Average Eggs Per Female The average number of eggs per female, by the month, for 1919, is given in Table 14. The maximum number, '7' 1, was produced in June, with a mean temperature of 85.2 degrees F. A minimum average number of 4'7 eggs was noted in November, with a mean temperature of 79 degrees F. The average number of eggs per month for each female during the entire year was 56, in an average mean monthly temperature of 83.2 degrees F. Table 14 Average Eggs per Female Average No. of Date Temperature, No. eggs Total No. females mean per female of eggs oviposltlng 1919 January . . . . . . . . . . . . . . . . . . . . . . . . . . 79.1 57 909 16 February . . . . . . . . . . . . . . . . . . . . . . . . . 78 .8 48 817 17 March . . . . . . . . . . . . . . . . . . . . . . . . . . . 80.4 52 722 14 April . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82.4 52 574 11 May . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84.7 67 672 10 June . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85 .2 71 571 8 July . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92.3 58 407 7 August . . . . . . . . . . . . . . .' . . . . . . . . . . . . 90.8 50 302 6 September . . . . . . . . . . . . . . . . . . . . . . . . 85.1 67 600 9 October . . . . . . . . . . . . . . . . . . . . . . . . . . 84.5 61 861 14 November . . . . . . . . . . . . . . . . . . . . . . . . 79 .0 47 282 December . . . . . . . . . . . . . . . . . . . . . . . . 76.9 52 628 12 48 BULLETIN No. 308. Thus under laboratory conditions each female produced an average of nearly two eggs per day for the entire year. Fortunately, under natural conditions the average number per female is considerably smaller, because low temperatures have a positive effect in diminishing the rate of oviposition. Proportion of Sexes From November 3, 1918, to January 25, 1919, 1473 weevils were reared in the laboratory from tubers infested under natural conditions. About 49.5 percent. of the total number, or 727, were males; slightly over 5O per cent., or 746, were females. Collections made during the active season in the field resulted in taking approximately an "equal number of each sex. Table 15 shows the proportion of males and females as they emerged daily in the laboratory. Table 15 Proportion of Sexes‘ No. pf Date weevils Males Females emerged 1918 November 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 4 November 4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 7 6 November 5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 9 5 November 6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 9 13 November 7. . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 27 -9 18 November 8 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 12 13 November 11 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80 35 45 November 13 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 125 60 65 November 14 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5O 21 29 November 15 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61 31 30 November 16 . . . . . . . . . . . f . . . . . . . . . . . . . . . . . . . . . 42 24 18 November 17 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83 32 51 November 18 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60 34 26 November 19 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91 45 46 November 20-21 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 248 119 > 129 November 22 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69 . 29 4O November 23 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58 36 22 November 24-25 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115 59 56 November 26 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82 39 43 November 27 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53 29 24 November 28-29 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54 33 21 November 30 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38 19 19 1919 ‘ January 22 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 17 8 January 25 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 16 15 Protection ' All of the immature stages of the sweet potato weevil are afforded an excellent protection by the habits of the insect. The egg is deposited in an especially prepared cavity, the entrance to which is sealed, secur- ing it effectively from injury by sudden changes in temperature or attacks of enemies. Normally the entire larval and pupal stages are spent within the food plant, and they are protected likewise from the attack of parasites and adverse climatic conditions. Undoubtedly the red and metallic blue coloration of the adult weevil protects it from many enemies. The general texture of the weevil is hard and this probably results in making it an undesirable source of food supply for predacious enemies. Adults avoid danger most com- monly by feigning death. Upon disturbance they drop to the ground and remain motionless, frequently feigning death for several minutes. THE SWEET POTATO WEEvrL. 49 So long as they remain motionlesscthey are very difficult to see‘, espe- cially on loose, dark-colored soils. Adults are further protected by their general secretive habits and coloration, which blends effectively with the vines and foliage. While feeding in the field they are rarely observed on the plants unless very close examination is made. Adaptive Uapiacity The sweet potato weevil is restricted to the sweet potato and several closely related plants for its food supply. Some of the wild species of plants of the Uomzoloulus family probably comprised its natural food plants, but at the present time the sweet potato is preeminently the most important source of food. From the time that the insect was first described, nearly two-thirds of a century elapsed betore it was reported as attacking sweet potatoes. Generally the latter is considered to be an acquired food plant. All varieties of sweet potatoes are SHbjQClZ to attack, and when tubers are not accessible in the field, the insect feeds and propagates on the vines, without apparent inconvenience. According to some experiments conducted by Conradi, the weevil can be forced to accept, for food, plants other than those on_ which it normally feeds. There is no available record, however, of the weevil’s completing its life cycle on any food plant other than the sweet potato or some allied species. The weevil has a pair of fully developed wings, and is capable of at least limited flights. Up to this time, however, observations seem to indicate that this means of travel is not resorted to, even under the most adverse conditions. Flight The weevil has fully developed wings, and several instances of flights have been recorded heretofore. During the time of these observations a number of cases of the weevil in short flights have been noted. Three of the flights which were first observed occurred in the laboratory dur- ing February, 1920. These weevils had been confined in tin boxes, and when the latter were opened the weevils, after spreading their wings several times, began flight of their own accord. The greatest distance covered in any case was not over fifty feet. Although the wings are moved very rapidly while in the air, the speed attained by the weevil is only moderate, and its course of flight can be, readily followed. Many attempts to induce flight were made with a large number of weevils, and the results obtained from these experiments prove that the weevil has the ability to make at least limited intermittent flights, either in the open or in the confinement of the laboratory. The details of several observations on this important subject are given herewith. On May 30, 1922, a male weevil with its wings pro~ truding from beneath the elytra was tossed into the air, and it began to fly upward, taking a spiral course until it reached the ceiling, where it continued to fly in circles, until it became entangled in a spider-web. Up to the time of its interruption the flight was continuous for slightly more than one minute. The weevil was released and again tossed into the air, and after several attempts it began another flight which was 50 BULLETIN No. 308. directed across the room in a more or less straight course until it struck the opposite wall and fell to the floor. The distance covered during this flight was approximately twenty feet. On the same day another male weevil was observed to begin flight on being tossed into the air. It began to fly spirally upward, then sud- denly downward, when it again resumed its former course. The inter- esting feature of this observation is the duration of flight. In con- finement of the laboratory this weevil remained flying in the air for a period of two and one-half minutes. Many other flights of less dura- tion, that were made by different individuals, have been observed. ‘Male weevils Were much more easily induced to fly by being tossed in the air than the females. On May 31., 1922, 15 male specimens were released in the open. There was a brisk south Wind. The flight of the first Weevil was directed gradually upward inthe windward direction and its course was followed for more than 60 yards before it disappeared. This was the longest continuous flight noted in these observations. More commonly the weevils flew spirally upward, and attained a height of 30 feet or more before they were lost from view. Several of the flights were short, being directed obliquely towards the ground. No weevils were observed in flight, at any" time, during the active season in the field. These results indicate, however, that flight is a possible means of dissemination. Feigning; Death When the weevil is suddenly disturbed or becomes frightened, it feigns death. This habit is the most important means it has for es- caping danger. In feigning death the Weevil falls upon its side or back, with the legs left either widely spread or slightly drawn together under the body, and the antennae retracted along the ventral side of the beak and head. In this position the weevil may remain motionless for a period of four or five minutes, but if further disturbed, it quickly re- covers its footing and attempts to escape by running for any available protection. In cases of undue fear the weevil will oftentimes apparently “forget” to feign death, and will depend wholly upon its running ability to elude its enemies. The death-feigning habit makes it very difficult to observe the weevil inthe sweet potato draw-bed, or among the vines and tops of growing plants in the field. Reproduction Sexual Attraction and C0puZati0n.—To ascertain the extent of sexual attraction, several virgin females were placed in small wire cages, and active males were released near these cages at distances varying from a few inches to several feet. In no case was there an immediate definite attraction for the male weevils to the cages. At the conclusion of a 3-hour period the attraction was no more pronounced, and male insects seemed more intent upon secreting themselves than searching for females. The females were then placed in four-ounce tin salve boxes together with the males and copulation was noted several hours there- after. The general conclusion is that sexual attraction is not very highly developed in this insect, and sexes are attracted only when they THE SWEET POTATO WEEVIL. 51 actually meet or come into contact with each other, which often occurs because of the insect’s sedentary habits. Several copulations usually occur at irregular intervals during the life of the females. The exact duration of the act was not determined, but several pairs of weevils were noted in copula for a period of at least one hour and ten minutes. During the act of mating the weevils remain quiet and motionless. However, if disturbed, the female im- mediately begins to crawl, carrying the male with her, or, as is more frequently the case, they separate quickly to avoid danger. There is little question but that both polyandry and polygamy exists among the adults of the sweet potato weevil, since a number of matings frequently occur during the lifetime of the weevil. Period Between M atviritg/ and U0pu.la.ti0n.—Normally transformation tothe adult occurs in the larval burrow or pupal cell, within the tuber. Immediately after becoming an adult, the weevil is very soft and help- less, and a period of several days is necessary before it attains a suffi- cient degree of hardness and strength for emergence. After the weevil emerges, a feeding period is also necessary before it becomes sexually matured. A number of recently emerged females were confined without food with sexually matured males, for periods ranging from two to five days. They were then placed on fresh tubers, and in each case feeding began immediately, but no oviposition occurred. When the females were allowed to feed for a day or more, and males were then confined with them, oviposition generally began soon thereafter. All the ob- servations made in this connection seem to indicate that mating never takes place prior to feeding. The exact age at which copulation nor- mally takes place has not been determined. In Table 16 are given the periods from emergence to first oviposition. These results give some idea of the time from maturity to copulation. It should be noted, however, that these periods begin with emergence, and do not include the additional period from the date of transforma- tion to the adult stage to emergence from the tuber. FertiZity.-—From all observations made on this point it appears that one successful mating is suflicient to insure the fertility of at least the average number of eggs deposited by the female. Several cases were noted in which all the eggs laid by a female were fertile after one union with a male. Successive matings, however, may take place after the initial fertilization has been effected. Generally, normal oviposition does not occur in. the case of unfertilized females, although several in- stances were observed where such individuals deposited eggs in the usual manner. None of these eggs hatched. More frequently the eggs of unfertilized females are deposited upon the surface of the tuber, but’ eggs thus exposed soon shrivel and dry, and have never been observed to hatch. Over the entire period of observations, the number of in- fertile eggs, among those deposited in a normal manner, was very small and did not effect a material reduction in the number of larvae pro- duced. O1’7ipO8’it’t0’fL.—Wltl1 the approach of warm Weather in the spring, the weevils become active in the field, and may begin oviposition in the 52 BULLETIN N0. 308. vines before the tubers have begun to develop. The eggs are laid in- variably in the lower portions of the vines near 0r just beneath the surface of the ground. The insect, however, seems to prefer the tuber for oviposition, and the latter is attacked as soon as it has attained a suflicient size. The act of oviposition is not preceded by any critical examination of the tuber for a favorable locality, or for ascertaining prior infesta- tion. Quite the contrary appears to be true. The eggs are laid promiscuously in all portions of the tuber, some contiguous and others widely scattered. Egg deposition Will take place readily in a tuber con- taining the insect in all of its stages of development, and in cases of severe infestation so many eggs may be deposited in a single tuber that many larvae perish for want of a sufficient food supply. All normally deposited eggs are placed in especially prepared cavities. The egg cavity 1's not as deep as the feeding puncture, but usually 1's greater in diameter, and is directed into the tuber at a more oblique angle. Table 16 Period from Emergence to Oviposition No Female emerged First egg Period, days 1919 1919 13 January 5 . . . . . . . . . . . . . . . . . . . . . . . . January 13 . . . . . . . . . . . . . . . . . . . . . . 8 14 January 5 . . . . . . . . . . . . . . . . . . . . . . . . January 13 . . . . . . . . . . . . . . . . . . . . . . 8 15 January 5 . . . . . . . . . . . . . . . . . . . . . . . . January 13 . . . . . . . . . . . . . . . . . . . . . . 8 16 January 5 . . . . . . . . . . . . . . . . . . . . . . . . January 12 . . . . . . . . . . . . . . . . . . . . . . 7 17 January 5 . . . . . . . . . . . . . . . . . . . . . . . . anuary 1 . . . . . . . . . . . . . . . . . . . . . . 12 18 January 31 . . . . . . . . . . . . . . . . . . . . . . . . February 9 . . . . . . . . . . . . . . . . . . . . . . 9 19 pril . . . . . . . . . . . . . . . . . . . . . . . . . . . April 8 . . . . . . . . . . . . . . . . . . . . . . . . . 1 20 April 8 . . . . . . . . . . . . . . . . . . . . . . . . . . . April 16 . . . . . . . . . . . . . . . . . . . . . . . . . 8 21 May 26 . . . . . . . . . . . . . . . . . . . . . . . . . . . May 28 . . . . . . . . . . . . . . . . . . . . . . . . . 2 22 May 3O . . . . . . . . . . . . . . . . . . . . . . . . . .. May 31 . . . . . . . . . . . . . . . . . . . . . . . .. 1 23 July . . . . . . . . . . . . . . . . . . . . . . . . . . . July . . . . . . . . . . . . . . . . . . . . . . . . . 3 24 July 5 . . . . . . . . . . . . . . . . . . . . . . . . . . . July 8 . . . . . . . . . . . . . . . . . . . . . . . .. 3 25 June 28 . . . . . . . . . . . . . . . . . . . . . . . . . .. July 1 . . . . . . . . . . . . . . . . . . . . . . . .. 3 26 August 3 . . . . . . . . . . . . . . . . . . . . . . . . . . August 8 . . . . . . . . . . . . . . . . . . . . . . . 5 27 August 3 . . . . . . . . . . . . . . . . . . . . . . . . . . August 19 . . . . . . . . . . . . . . . . . . . . . . . 16 28 August 3 . . . . . . . . . . . . . . . . . . . . . . . . . . August 19 . . . . . . . . . . . . . . . . . . . . . . . 16 29 August 3 . . . . . . . . . . . . . . . . . . . . . . . . . . August 25 . . . . . . . . . . . . . . . . . . . . . . . 22 30 July 30 . . . . . . . . . . . . . . . . . . . . . . . . . . . ugust 1 . . . . . . . . . . . . . . . . . . . . . . . 2 31 July 30 . . . . . . . . . . . . . . . . . . . . . . . . . . . August 1 . . . . . . . . . . . . . . . . . . . . . . . 2 32 August 29 . . . . . . . . . . . . . . . . . . . . . . . . . September 24 . . . . . . . . . . . . . . . . . . . . 26 33 August 30 . . . . . . . . . . . . . . . . . . . . . . . . . September 24 . . . . . . . . . . . . . . . . . . . . 25 34 September 3 . . . . . . . . . . . . . . . .- . . . . . . September 10 . . . . . . . . . . . . . . . . . . . . 7 35 September 3 . . . . . . . . . . . . . . . . . . . . . . September 23 . . . . . . . . . . . . . . . . . . . . 20 36 September 3 . . . . . . . . . . . . . . . . . . . . . . . September 10 . . . . . . . . . . . . . . . . . . . . 7 37 September 8 . . . . . . . . . . . . . . . . . . . . . . . September 1O . . . . . . . . . . . . . . . . . . . . 2 38 October 3 . . . . . . . . . ._ . . . . . . . . . . . . . . . October 4 . . . . . . . . . . . . . . . . . . . . . . 1 39 October 3 . . . . . . . . . . . . . . . . . . . . . . . . . October 4 . . . . . . . . . . . . . . . . . . . . . . 1 40 October 3 . . . . . . . . . . . . . . . . . . . . . . . . . October 4 . . . . . . . . . . . . . . . . . . . . . _ 1 41 October 8 . . . . . . . . . . . . . . . . . . . . . . . . . October 9 . . . . . . . . . . . . . . . . . . . . . . 1 42 October 8. . . _. . . . . . . . . . . . . . . . . . . . . . October 10 . . . . . . . . . . . . . . . . . . . . . . 2 43 October 8 . . . . . . . . . . . . . . . . . . . . . . . . . Oct.ober . . . . . . . . . . . . . . . . . . . . . . 1 44 November 24 . . . . . . . . . . . . . . . . . . . . . . November 27 . . . . . . . . . . . . . . . . . . . . 3 45 November 24 . . . . . . . . . . . . . . . . . . . . . . November 27 . . . . . . . . . . . . . . . . . . . . 3 46 November 24 . . . . . . . . . . . . . . . . . . . . . . November 27 . . . . . . . . . . . . . . . . . . . . 3 47 November 22 . . . . . . . . . . . . . . . . . . . . . . November 27 . . . . . . . . . . . . . . . . . . . . 5 48 November 24 . . . . . . . . . . . . . . . . . . . . . . November 27 . . . . . . . . . . . . . . . . . . . . 3 49 November 24 . . . . . . . . . . . . . . . . . . . . . . November 27 . . . . . . . . . . . . . . . . . . . . 3 920 1920 50 January,20 . . . . . . . . . . . . . . . . . . . . . . . . January 30 . . . . . . . . . . . . . . . . . . . . . . 1O 51 January, 20 . . . . . . . . . . . . . . . . . . . . . . . . February 2 . . . . . . . . . . . . . . . . . . . . . . 13 52 January‘ 20 . . . . . .- . . . . . . . . . . . . . . . . . . January 26 . . . . . . . . . . . . . . . . . . . . . . 6 53 January 2O . . . . . . . . . . . . . . . . . . . . . . . . January 26 . . . . . . . . . . . . . . . . . . . . . . 6 When the female has completed the egg cavity she turns about and. begins to feel for the entrance of the cavity with the tip of the abdomen by moving it from side to side. Usually the opening is readily located, THE SWEET POTATO WEEvrL. 53 but sometimes considerable time is spent before she is successful. After the egg cavity has been located with the tip of the abdomen, the ovipositor is protruded into it. At this time the female stands in a humped position, with the legs widespread and the claws firmly im- bedded. In this position she may remain motionless for a brief period. Then by a series of abdominal contractions the egg is forced into the cavity, sometimes to the very bottom, but quite frequently only part Way. Invariably the upper end of the egg is covered, and the entrance of the cavity is filled, with a quantity of white mucilaginous material, WlllCh pardens and becomes darker upon exposure. This seals the egg cavity and at the conclusion of the act of oviposition the female leaves Without turning to inspect her work. The time consumed during the act of oviposition varies considerably with the season and the individual. After the egg cavity has been completed it may require eight minutes to one hour, or more. No extended observations were made during the period of these studies to determine the average time required for oviposition. In the laboratory, oviposition took place throughout the entire year. Under natural conditions, however, no insects were observed depositing eggs during the winter months at College Station, and the general con- clusion is that few eggs are laid during this season, even though Weevil activity is manifested on xvarm days. Period from Emergence to Oviposition.—The age at which oviposition begins varies greatly with the individual and the season, as will be noted in the accompanying table. Normal oviposition does not take place until fertilization has been accomplished, but generally begins soon thereafter. The age of the female at which oviposition begins is, there- fore, dependent upon the time at which successful fertilization is efieeted. Observations in this connection, extending from January, 1919, to January, 1920, were made on 41 pairs of weevils. The female in each case, immediately after emergence, was placed on a fresh tuber, to- gether with a male, and the first egg production was noted. The results obtained from these observations are given in Table 16. The length of the period ranged most frequently from 1 to 5 days. The average age of the <11 females at the beginning of oviposition was 6.9 days. Period of Ooip0siti0n.—After an average feeding period of about '7 days, oviposition usually begins, and is continued more or less regularly, depending upon prevailing temperatures, until shortly before the death of the female. In a number of cases the females deposited eggs on the date of their death; however, more frequently a period of one to several days intervenes between last oviposition and death. The periods of oviposition, as they occurred from December 16, 1918, to January 26, 1920, are given in Table 1'7. It will be noted that the periods vary greatly with the individual and the_ season. At temperatures which maintain the maximum weevil activity the period of oviposition is gen- erally much shorter. During cold weather egg laying may cease en- tirely, but is resumed when a rise in temperature occurs. This often results in a great prolongation of the oviposition period. The length of the period ranged from 30 to 209 days. yThe average period of oviposi- tion of 43 females kept under observation was 104.2 days. 54 BULLETIN No. 308. Table 17 Period of Oviposition Period, Temperature, No First egg Last egg ays mean 1918 1919 1 December 16 . . . . . . . . . . . . . . . . . April 18 . . . . . . . . . . . . . . . . . . . 124 80.5 2 December 19 . . . . . . . . . . . . . . . . . March . . . . . . . . . . . . . . . . . . 102 80.2 3 December 16 . . . . . . . . . . . . . . . . . February 2 . . . . . . . . . . . . . . . . 49 80.7 4 December 16 . . . . . . . . . . . . . . . .. June 8 . . . . . . . . . . . . . . . . . . . . 175 81.8 *5 December 16 . . . . . . . . . . . . . . . . April 28 . . . . . . . . . . . . . . . . . . . 134 80.6 *6 December 18 . . . . . . . . . . . . . . . . . February 11 . . . . . . . . . . . . . . . 56 79.5 7 December 18 . . . . . . . . . . . . . . . . . July 14 . . . . . . . . . . . . . . . . . . . 209 83.3 8 December 23 . . . . . . . . . . . . . . . . March 10 . . . . . . . . . . . . . . . . . 78 80.8 *9 December 19. . . . . . . . . . . . . . . February 20 . . . . . . . . . . . . . . . 64 80.2 1O December 19 . . . . . . . . . . . . . . . . April 9 . . . . . . . . . . . . . . . . . . . . 112 80.3 11 December 20 . . . . . . . . . . . . . . . . March 14 . . . . . . . . . . . . . . . . . . 85 80.6 12 DecembgigO . . . . . . . . . . . . . . . . May 19 . . . . . . . . . . . . . . . . . . . 151 81 .3 13 January 13 . . . . . . . . . . . . . . . . . . August 2 . . . . . . . . . . . . . . . . . . 202 84.6 14 January 13 . . . . . . . . . . . . . . . . . . April 8 . . . . . . . . . . . . . . . . . . . . 86 79.6 *15 January 13 . . . . . . . . . . . . . . . . . . January 20 . . . . . . . . . . . . . . . . 8 79.5 16 January 12 . . . . . . . . . . . . . . . . . . April . . . . . . . . . . . . . . . . . . . . 81 79.4 17 January 17 . . . . . . . . . . . . . . . . . . May . . . . . . . . . . . . . . . . . . . 126 81.8 18 February 9 . . . . . . . . . . . . . . . . .. July 11 . . . . . . . . . . . . . . . . . . .. 153 83.8 19 April 8 . . . . . . . . . . . . . . . . . . . . . . July 19 . . . . . . . . . . . . . . . . . .. 103 86.1 20 April 16 . . . . . . . . . . . . . . . . . . . .. July 9 . . . . . . . . . . . . . . . . . . . .. 85 85.8 21 May 28 . . . . . . . . . . . . . . . . . . . . . November 21 . . . . . . . . . . . . . . 178 86.1 22 May 31 . . . . . . . . . . . . . . . . . . . . . ugust . . . . . . . . . . . . . . . . . . 7O 90.5 23 July 5 . . . . . . . . . . . . . . . . . . . . . . . August 10 . . . . . . . . . . . . . . . . . 37 91.5 24 July 8 . . . . . . . . . . . . . . . . . . . . . . October 17 . . . . . . . . . . . . . . . . 102 88.2 *25 Julyl . . . . . . . . . . . . . . . . . . . . . .. y3 . . . . . . . . . . . . . . . . . . . .. 3 90.5 26 August 8 . . . . . . . . . . . . . . . . . . . October 19 . . . . . . . . . . . . . . . . 73 86.8 *27 August 19 . . . . . . . . . . . . . . . . . August 19 . . . . . . . . . . . . . . . . . 1 90.0 28 August. 19 . . . . . . . . . . . . . . . . . . . October 6 . . . . . . . . . . . . . . . . . 49 87.6 29 August 25 . . . . . . . . . . . . . . . . . . . March 14, 1920 . . . . . . . . . . . . 203 79.5 *30 August 1 . . . . . . . . . . . . . . . . . . August 10, 1919 . . . . . . . . . . . 10 93.9 *31 August 1 . . . . . . . . . . . . . . . . . . . . August 12, 1919 . . . . . . . . . . . 12 93.6 32 September 24 . . . . . . . . . . . . . . . . February 9, 1920 . . . . . . . . . 139 80.5 33 September 24 . . . . . . . . . . . . . . . . February 11, 1920 . . . . . . . . . 141 80.3 *34 September 10 . . . . . . . . . . . . . . . . September 15, 1919 . . . . . . . . 6 88.4 *35 September 23 . . . . . . . . . . . . . . . . September 30, 1919 . . . . . . . . . 8 81 .6 36 September 10 . . . . . . . . . . . . . . . . January 18, 1920 . . . . . . . . . . 131 80.9 37 September 10 . . . . . . . . . . . . . . . . October 14, 1919 . . . . . . . . . . 35 84.7 38 October 4 . . . . . . . . . . . . . . . . . . December 6. 1919 . . . . . . . . . 64 84.8 *39 October 4 . . . . . . . . . . . . . . . . . . October 23, 1919 . . . . . . . . . . 20 80.5 40 October 4 . . . . . . . . . . . . . . . . . . November 2, 1919 . . . . . . . . . 30 81 .2 41 October 9 . . . . . . . . . . . . . . . . . . January 11, 1920 . . . . . . . . . . 95 79.4 *42 October 10 . . . . . . . . . . . . . . . . . . October 11, 1919 . . . . . . . . . . 2 85.7 43 October 9 . . . . . . . . . . . . . . . . .. Novemlaéagoll 1919 . . . . . . .. 35 82.2 44 November 27 . . . . . . . . . . . . . . . . February 4 . . . . . . . . . . . . . . . . 70 78.3 45 November 27 . . . . . . . . . . . . . . . . March 30 . . . . . . . . . . . . . . . . . 125 76.6 46 November 27 . . . . . . . . . . . . . . . . March 22 . . . . . . . . . . . . . . . . . . 117 76.4 47 November 27 . . . . . . . . . . . . . . . . March 30 . . . . . . . . . . . . . . . . . 125 76.6 48 November 27 . . . . . . . . . . . . . . . . February 11 . . . . . . . . . . . . . . . 77 77.6 49 Novemlbggo27 . . . . . . . . . . . . . . . . April 26 . . . . . . . . . . . . . . . . . . . 152 77.3 50 January 3O . . . . . . . . . . . . . . . . . . April 26 . . . . . . . . . . . . . . . . . . . 88 78. 1 *51 February 2 . . . . . . . . . . . . . . . . . . February 13 . . . . . . . . . . . . . . . 12 79.1 52 January 26 . . . . . . . . . . . . . . . . . . April 14 . . . . . . . . . . . . . . . . . . . 80 76.9 53 January 26 . . . . . . . . . . . . . . . . . . April 26 . . . . . . . . . . . . . . . . . . . 92 77.5 *Incomplete record. Rate 0f Ovip0siti0n.—In Table 18 are given the daily observations made on the rate of oviposition in the laboratory. The rate at which the eggs are deposited often varies considerably from day to day with the same female, under similar conditions. There appears to be no regularity in the number of eggs deposited for a given period. The number of eggs produced during a 24-hour period ranged from 1 to 17. This maximum number was obtained but once during the entire observa- tions, and it occurred on January 19, 1920, at a mean temperature of 89 degrees F. From 3 to 9 eggs Were frequently laid during Warm Weather in a 24-hour period. The period between egg depositions in~ creases as the limit of the average egg quota is approached, and becomes more protracted as the period of oviposition nears completion. THE SWEET POTATO WEEVIL. Table 18 Rate of Oviposition - n ¢ . . . - . . - . . - . . . - . . . . . . . . . Q . . . . . . . .H.H.M0000010211234333 . . . . HM0000001001011100 2112121223434222112544 . - Q - - . . ¢ . - Q Q - » . . o 7 1 6 1 5 1 4 1 3 1 m u 1 ..M00311422123242 110112103141O110201221 1 .. m N ..M02300221114433 1202112132334022134303 m 9 H“M02210711262200 0223210131211210022242 r 8 ..M00000110213354 030214O122235022234443 i .. M 7 ..M12122032212143 1021121213334113132343 6 ..M22311611273220 1022221121144032243435 5 M152251031O372140 010l120122311310224316 4 M5534511211132440 121222122l225141043075 3 M7443611500244430 0002131121232032031253 2 M0001110022234434 020103112l2232ll201132 1 M5343711422283330 0211131222245222435435 n 555 55 55 5-3-5 55.55 5 a 14564651892380196 2134692548232476879211 W 87888888778878888 8777778777888877777888 m t - m m 52705977760236558 4582587785018733632653 W M 77787777778877787 7667777667887777777777 m e . T M 76334435934534835 08878073025572190l6870 M 87999998788888899 9777788888888987888889 HUHUHHHUHHHHUHHHHQHHH“Hnuuununuuuuununun - . - . - . . - . . - . . . . -.1.-...-..-..........-. . . . . . . . . . . . . . . . ..Qu...................... m “Influx“I”In“Hlnnuunnnunnnunnnunnnnnn a 56789012345678901 .Z&¢5&T&&&.2&L5&T&&Q.2 D 1111l222222222233 1 1Hl111l1112fl2 . - - . ¢ Q Q . - o ¢ ¢ - - ¢ - . - Q ¢ u u M—-Mated. D—-Died. Ir-Lost. BULLETIN N0. 308. 56 Table 18—Rate of Oviposition-Continued PairNumber 1 2 3 4 5 6 7 8 9101112131415161718 4209212231011324222243211.04302102122132 4133234223312333323333154.510321012021122 00D . . . . 1011011..12110302132022011110203211104211 2.13302422211132422324244342205111132344 41.4423344221101323332234321321113233232 102223011210203011123132212301113122243 34.210232322032003322133332403132112132244 224323222110102110122232221l1L . . . . . . . . . 442131413212122422222525522323211222332 322219024.122133342123334.4.342303112222132 338222344221223332230L . . . . . . . . . . . . . . . . . 4332223900220101122213212229011300021202902 4322021901222223221321334333303320222143 123203242320000000000000000000000000000 533232344.220431332334544432102211123254 Temperature M ax . Min. Mean 5 55555 55 555 5555 55 5'? 0005779252971000029757300024 0077777000000777007000077770000000000 Date . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . - - - . . - . . . . . - . - - . . . . . - . . . . . . . . . . . . . . . . . . - . . . . . . . - . . . - - . . . . . . . . - . . . . . . . . . . . - . . - . . . . - . . . . . . . . . - . . . . . . . . . . . . - . . . . - . . . . . - . . . . - . . . - . . - - . - - - - . . . - - - . - - . ~ . . . . . M——M ated . D—Died . L—-Lo st. THE SWEET POTATO WEEVIL. Table 18—-Rate of Oviposition—Continued 57 D t Temperature Pair Number ae Max. Min. Mean 2 3 4 5 7 81011 1213141617181920 1919 March 3 . . . . . . . . . . .. 95 85 90 5 3 0 4 3 2 4 5 5 5 5 0 1 3 0... March 4 . . . . . . . . . . .. 101 84 92.5 3 3D 2 O 3 4 4 2 5 5 O O 4 6... March 5 . . . . . . . . . . .. 98 82 9O 6 1.. 2 4 3 4 2 2 3 2 1 O 4 4... March 6 . . . . . . . . . . .. 90 77 83.5 3 3.. 4 2 3 1 3 4 4 2 1 O 0 3... March 7 . . . . . . . . . . .. 90 77 83.5 1 1.. 1 1 1 3 2 1 3 1 0 1 2 3... March 8 . . . . . . . . . . .. 85 8O 82.5 2 1.. l 2 2 O 1 2 2 2 1 1 2 2... March 9 . . . . . . . . . . .. 80 73 76510.. O 2 1-0 1 1 2 2 O 012... March 1O . . . . . . . . . .. 77 72 74.5 3 2 .. 2 1 2 1 1 O 3 2 0 O 1 2 ... 85 73 79 21.. 212 0 2 0 2 210 3 1... 85 77 81 41.. 1310 2 O 2 210 2 2... 78 77 77.5 3 2.. 4 1 2 O 2 0 4 2 1 1 1 4... 86 77 81.5 2 1.. 12 2 0 2 1 2 2 1 0 1 2... 82 80 81 2 2.. 3 2 2 0 3 0 4 3 212 3... V83 8O 81.5 2 2.. 3 2 2 0 3 0 3 2 2 0 1 2... 81 78 79.51 1.. 1O 2 O 1 O 3 2 2 O O 1... 84 73 78.5 2 1..1 2 O 0 2 O 2 1 0 012... 78 74 76 21.. 1110 2 O 3 2 012 2... 78 75 76.510.. 11 3 O 2 O 2 1 0 1 2 3... 83 71 77 2 1.. 210 0 2 0»1 3 2 012... 86 78 82 3 2.. 2 2 2 0 3 0 3 2 2 2 2 2... 81 78 79.5 2 2 .. 2 2 2 O 3 0 3 2 1 2 2 1.._. 8O 76 78 2 2.. 1 3 1 O 1 O 2 2 1 O 1 3... 80 79 79.5 2 1..1 1 O O 3 O 1 1 O O 1 2... 79 75 77 1 1.. 12 3 O 0 0 1 2 0 0 0 O... 77 71 74 -3 3.. 2 1 2 O 4 0 3 1 2 O 1 4... 86 72 79 11.. ll 1 0 1 0 3 1 1 O 1 2... 88 78 83 31.. 3 1 3 0 3 0 2 310 2 2... 80 76 78 2 1.. 2 1 2 0 2 0 2 2 0 0 2 2... 84 76 8O 10.. 111010110 211.... 85 75 8O 10.. l 2 1 O 1 O 1 2 O 010.... 83 75 79 2 0.. 2 010 2 0 2 1 0 2 0 3.... 77 73 75 10.. 3 2 1 0 2D 2 3 O O 2 1.... 85 75 80 0 0.. 0 1 0 O 2.. 2 O 0 0 0 0.... 84 75 79.5 2 0.. 4 3 3D 3. 4 4 1D 3 4.... 82 78 8O 2 0.. 4 2 2.. 2. 3 3 1.. 3 3.... 84 81 82.5 2 0.. O 3 2 2.. 3 2 0. 3 2M.. 88 83 85.5 3 0.. 3 3 2. 1.. 2 31. 2 2 1M 86 81 83.5 2 0.. 3 2 1. 1..1 2 O. 2 2 O O 86 71 78.5 2 0.. 2 2 2. 0.. 2 2 O. 1 110 M—Mated. D-Died. L-Lost 58 BULLETIN N0. 308. Table 18—Rate of Ovipositiom-Continued D t Temperature Pair Number ae Max. Min. Mean 1 2 4 5 7 101213 14 1718 19 20 _ 1919 Apql 11 . . . . . . . . . . . . . . . . . . . . . .. 87 7O 78.5 1 O 2 2 O O 2 2 O 1 3 O O Aprgll2 . . . . . . . . . . . . . . . . . . . . . .. 9O 73 81.5 3 0 3 3 1 0 3 4 0 2 2 2 0 Apql13 . . . . . . . . . . . . . . . . . . . . . .. 93 77 85 2022002301220 Aprgll4 . . . . . . . . . . . . . . . . . . . . . .. 95 81 88 1D32004302420 Apr;l15 . . . . . . . . . . . . . . . . . . . . . .. 88 80 84 4.. 12004202000 Apqllfi . . . . . . . . . . . . . . . . . . . . . .. 92 80 86 1. 1 lODl200235 Aprgll7 . . . . . . . . . . . . . . . . . . . . . .. 87 72 79.5 0. 0 1 0.. 2 2 0 0 2 5 2 Apr;ll8 . . . . . . . . . . . . . . . . . . . . . .. 87 75 81 2. 2 1 0.. 31D 12 4 4 prgll9 . . . . . . . . . . . . . . . . . . . . . .. 90 77 83.50. 1 20. 33.. 1 321 Aprgl20 . . . . . . . . . . . . . . . . . . . . . .. 9O 79 84.5 0. 1 2 0. 3 2. 1 2 2 1 Apr1l21 . . . . . . . . . . . . . . . . . . . . . . .. 89 8O 84.5 0. 2 3 O. 2 3. 3 2 4 2 Apr1l22 . . . . . . . . . . . . . . . . . . . . . . .. 90 77 83.5 0.. 2 2 0. 3 4. 2 2 4 1 April23 . . . . . . . . . . . . . . . . . . . . . .. 88 80 84 0.. 220. 33. 3316 April24 . . . . . . . . . . . . . . . . . . . . . .. 9O 80 85 0.. 240.. 24. 1 344 pril25 . . . . . . . . . . . . . . . . . . . . . .. 90 77 83.5D.. 320.. 53. 2212 April26 . . . . . . . . . . . . . . . . . . . . . .. 89 81 85 45 1.. 54.. 3344 Aprjl27 . . . . . . . . . . . . . . . . . . . . . .. 87 78 82.5. 3 4 1 .. 4 3.. 2 2 4 4 Apr1l28 . . . . . . . . . . . . . . . . . . . . . .. 93 85 89 . 4 3 0.. 2 4.. 4 3 3 3 April29 . . . . . . . . . . . . . . . . . . . . . .. 90 84 87 . 4 0 0.. 3 2.. 2 2 2 2 April3O . . . . . . . . . . . . . . . . . . . . . .. 89 76 82.5. 3.00.. 34.. 4444 May 1 . . . . . . . . . . . . . . . . . . . . . . .. 87 78 82.5. 300.. 34.. 3334 May 2 . . . . . . . . . . . . . . . . . . . . . . .. 93 80 86.5. 6 L 0.. 5 5.. 5 5 1 5 May3 . . . . . . . . . . . . . . . . . . . . . . .. 92 85 88.5.. 4.. 4.. 53.. 4434 May4 . . . . . . . . . . . . . . . . . . . . . . .. 89 82 85.5.. 3. 3.. 53.. 3433 May5 . . . . . . . . . . . . . . . . . . . . . . .. 90 86 88 .. 4. 2..43.. 1233 May6 . . . . . . . . . . . . . . . . . . . . . . .. 88 84 86 .. 1. 2..23.. 2323 May7 . . . . . . . . . . . . . . . . . . . . . . .. 85 75 80 .. 2. 3.. 21.. 4124 May8 . . . . . . . . . . . . . . . . . . . . . . .. 81 78 79.5.. 2. 1.. 23.. 2121 May9 . . . . . . . . . . . . . . . . . . . . . . .. 78 76 77 .. 1..2..22.. 1121 May10 . . . . . . . . . . . . . . . . . . . . . . .. 78 75 76.5.. 1.. 2.. 2 1.. 1 1 1 1 ayll . . . . . . . . . . . . . . . . . . . . . . .. 78 71 74.5.. 2..2..21..101 1 May12 . . . . . . . . . . . . . . . . . . . . . . .. 81 77 79 .. 3.. 1.. 22.. 1221 May13 . . . . . . . . . . . . . . . . . . . . . . .. 90 75 82.5.. 2..3..22..1122 ay14 . . . . . . . . . . . . . . . . . . . . . . .. 94 85 89.5.. 2.. 2.. 24.. 3143 May15 . . . . . . . . . . . . . . . . . . . . . . .. 92 86 89 .. 5.. 4.. 44.. 4345 ay16 . . . . . . . . . . . . . . . . . . . . . . .. 97 87 92 . 0.. 3.. 15.. 2434 ay17 . . . . . . . . . . . . . . . . . . . . . . .. 100 87 93.5.. 4.. 4.. 05.. 3463 May18 . . . . . . . . . . . . . . . . . . . . . . .. 98 80 89 . 4.. 3.. 05.. 3352 ay19 . . . . . . . . . . . . . . . . . . . . . . .. 91 85 n88 4.. 4.. 1 3.. 315 4 M-—-.Mated D-Died. L—L0st THE SWEET Potmmo WEEVIL. Table 18-—Rate of Oviposition——Continued D Temperature Pair Number ate Max Min. Mean 4 7 12 13 17 18 19 20 21 22 1919 May20 . . . . . . . . . .. 88 80 84 4 1 0 2 3 4 3 1 May2 . . . . . . . . . .. 93 76 84.5 0 4 0 2 1 2 2 4 May22 . . . . . . . . . .. 92 77 84.5 7 4 0 5 2 3 5 3 May23 . . . . . . . . . .. 93 8O 86.5 2 0 0 0 0 2 4 4 May24 . . . . . . . . . .. 87 85 86 1 3 0 5 0 3 3 4 May25 . . . . . . . . . .. 93 78 85.5 1 2 0 5 L 3 3 3 May26 . . . . . . . . . .. 86 82 84 4 3 0 5 4 5 4 M May 27 85 82 83.5 3 4 0 3 3 4 4 0 .... May28 . . . . . . . . . .. 94 81 87.5 4 6 0 5 4 4 5 8 May29 . . . . . . . . . .. 90 81 85.5 3 4 0 4 3 6 2 2 May 3 . . . . . . . . . . . 91 79 85 2 2 O 4 4 2 1 5 M May 31 . . . . . . . . . . . 90 76 83 2 4 0 4 6 8 4 4 2 June 1 . . . . . . . . . . . 88 82 85 1 2 0 3 3 2 4 3 2 June 2 . . . . . . . . . . . 93 85 89 4 1 0 1 2 2 3 0 3 June 3 . . . . . . . . . .. 90 77 83.5 0 2 0 5 0 2 2 1 2 June 4 . . . . . . . . . . . 9O 80 85 0 3 O 4 5 2 4 0 2 June 5 . . . . . . . . . . . . 91 80 85.5 0 2 O 2 3 3 4 1 4 June 6 . . . . . . . . . . . . 96 80 88 0 3 0 2 3 1 1 5 0 June 7 . . . . . . . . . . . 96 85 90.5 1 3 0 6 4 3 2 4 4 June 8 . . . . . . . . . . . 100 85 92.5 1 2 0 5 3 2 2 4 4 June 9 . . . . . . . . . . . 101 91 96 O 2 D 4 5 7 6 10 7 June 1O . . . . . . . . . .. 90 83 86.5 O O .. .. *4 3 3 1 0 1 June 11 . . . . . . . . . .. 89 76 82.5 0 0 2 2 2 3 4 1 June 12 . . . . . . . . . . . 96 85 90.5 D 2 3 2 3 2 1 3 June 13 . . . . . . . . . . . 95 85 90 . . . . 1 3 2 2 1 2 3 June 14 . . . . . . . . . . . 95 85 90 . 1 4 0 4 3 2 3 June 15 . . . . . . . . . . . 92 83 87.5 . 0 3 0 3 2 2 2 June 16 . . . . . . . . . . . 86 80 83 . 0 3 3 4 1 4 3 June 17 . . . . . . . . . . . 89 85 87 . 2 2 1 6 5 5 4 June 18 . . . . . . . . . . . 91 87 89 . 1 6 1 4 2 3 0 June 19 . . . . . . . . . . . 92 88 90 . 1 2 O 5 2 4 3 June 20 . . . . . . . . . . . 93 89 91 . 0 2 0 4 2 3 3 June 21 . . . . . . . . . . . 94 85 89.5 . 2 5 0 5 3 5 3 June 22 . . . . . . . . . .. 92 81 86.5 . '1 4 0 4 3 5 3 June 23 . . . . . . . . . . . 91 83 87 . 0 2 0 4 5 1 3 June 24 . . . . . . . . . . . 93 85 89 . 0 2 0 3 4 0 2 June 25 . . . . . . . . . . . 92 85 88.5 . 3 1 5 4 5 4 6 June 26 . . . . . . . . . . . 92 85 88.5 . 2 5 0 9 5 3 6 June 27 . . . . . . . _ . . . 92 85 88.5 . O 3 0 2 3 3 3 D—-Died. L—-Lost. M—-M ated . 60 BULLETIN l\'0. 308. Table 18-—'Rate of Oviposition-Continued D t Temperature Pair Number ae 4 Max. Min Mean 7 13 18 19 20 21 22 23 24 25 26 27 28 29 30 31 1919 June28 . . . . . . . . . . . . . . .. 92 84 88 4 2 1 5 3 2 June29 . . . . . . . . . . . . . . .. 93 87 90 32 1 5224.... June30 . . . . . . . . . . . . . . .. 95 88 9152503224.... Julyl . . . . . . . . . . . . . . .. 96 90 93 0533534.... July2 . . . . . . . . . . . . . . .. 96 91 93.53325424M.. July3 . . . . . . . . . . . . . . .. 96 94 95 12042340.. July4 . . . . . . . . . . . . . . .. 97 90 93.51204 1340.. July5 . . . . . . . . . . . . . . .. 97 93 95 03124441M July6 . . . . . . . . . . . . . . .. 97 90 93.50302333000......... July7 . . . . . . . . . . . . . . .. 96 89 92573620231 July8 . . . . . . . . . . . . . . .. 95 85 9O 22022330110......... July!-9 . . . . . . . . . . . . . . .. 97 91 94 O 1 1 2 1 42 1 Ju1y10 . . . . . . . . . . . . . . .. 98 9O 94 1112013030......... Julyll . . . . . . . . . . . . . . .. 100 91 95.502220 1 201 July12 . . . . . . . . . . . . . . .. 99 94 96.51202033000......... Julyl3 . . . . . . . . . . . . . . .. 99 97 98 01 O2032000......... July14 . . . . . . . . . . . . . . .. 100 98 99 1202032010......... July15 . . . . . . . . . . . . . . .. 99 94 96.50103031000......... July16 . . . . . . . . . . . . . . .. 100 92 96 01 01044000......... July17 . . . . . . . . . . . . . . .. 101 91 96 000301 1 1 July18 . . . . . . . . . . . . . . .. 96 90 93 0301054000......;... July19 . . . . . . . . . . . . . . .. 95 87 91 D2D1D43000........... July20 . . . . . . . . . . . . . . .. 96 93 94.5.. 2.. 0.. 42000.........:. July21 . . . . . . . . . . . . . . .. 96 93 94.5. 2 0. 56200.......... . July22 . . . . . . . . . . . . . . .. 94 92 93 1. 0. 55 1 July23 . . . . . . . . . . . . . . .. 92 90 91 3. 0. 5 7 3 1 0.. .. .. uly24 . . . . . . . . . . . . . . .. 90 86 88 .2. D.. 4023D............ July25 . . . . . . . . . . . . . . .. 96 87 91.5.. 3. 4232.............. July26 . . . . . . . . . . . . . . .. 97 89 93 .1. .5543. July27 . . . . . . . . . . . . . . .. 96 90 93 . 1. .4543. uly2 . . . . . . . . . . . . . . .. 95 85 90 .0.. .2330. Ju1y29 . . . . . . . . . . . . . . .. 96 91 93.5 . 2.. .7 4 3 1. .. .. .. .. July30 . . . . . . . . . . . . . . .. 98 91 94.5 . 0.. .5032..........MM July31 . . . . . . . . . . . . . . .. 97 92 94.5 . 2.. 7342.......... 00 Aug. 1 . . . . . . . . . . . . . . .. 97 92 94.5.1.. 3422.......... 14 Aug.2 . . . . . . . . . . . . . . .. 97 92 94.5.1.. 7243.......... 43 Al18-3 . . . . . . . . . . . . . . .. 96 90 93 .0.. 5454..MMMM13 Aug.4 . . . . . . . . . . . . . . .. 97 92 94.5.D.. 6462.. 0003026 Aug.5 . . . . . . . . . . . . . . .. 97 92 94.5.D.. 1022..O0OOO1 M-Mated. D-—-Died. Ir-Lost THE SWEET POTATO WEEVIL. Table 18——Rate of Oviposition—Continued D Temperature Pair Number ate Max. Min. Mean 212223M262728293031323334353637 1919 ' Aug.6 . . . . . . . . . . . . . . .. 97 91 94 0432000003............ Aug.7 . . . . . . . . . . . . . . .. 96 90 93 4502000010............ Aug.8 . . . . . . . . . . . . . . .. 97 90 93.53223100000........... Aug.9 . . . . . . . . . . . . . . .. 98 90 94 2035000000........... Aug10 . . . . . . . . . . . . . . .. 97 90 93.52035000010.......... . Augll . . . . . . . . . . . . . . .. 95 93 94 4004000001........... Aug12 . . . . . . . . . . . . . . .. 93 88 90.55000000001........... Aug13 . . . . . . . . . . . . . . .. 94 88 91 4DD70000L0........... Aug 14 . . . . . . . . . . . . . . .. 95 88 91.54.... 30000.. Aug 15 . . . . . . . . . . . . . . .. 95 90 92.55 . 40000 Aug.l6 . . . . . . . . . . . . . . .. 95 90 92.52. 50000 Aug.17 . . . . . . . . . . . . . . .. 94 90 92 1. 50000. _ Aug.18 . . . . . . . . . . . . . . .. 94 91 92.5 1. 1 0000. .. Aug.19 . . . . . . . . . . . . . . .. 95 85 90 4.. 4 1 2 1 0. Aug.20 . . . . . . . . . . . . . . .. 92 87 89.53.. 20000.............. .. Aug.21 . . . . . . . . . . . . . . .. 90 85 87.52.. 30000.. . Augs22 . . . . . . . . . . . . . . .. 90 84 87 3.. 30000.. .. Aug.-23 . . . . . . . . . . . . . . .. 85 81 83 2.. 3 0000.. . Aug.‘24 . . . . . . . . . . . . . . .. 87 85 86 2.. 20000.. - Aug.~25 . . . . . . . . . . . . . . .. 88 86 87 3.. 4 6D 713.. Aug.26 . . . . . . . . . . . . . . .. 91 80 85.5 1.. 40.. 23.. Aug.~27 . . . . . . . . . . . . . . .. 90 82 86 2.. 3 0. 0 3.. . Aug.28 . . . . . . . . . . . . . . .. 91 85 88 2.. 40. 03.. Aug.29 . . . . . . . . . . . . - . . .. 93 87 90 2.. 4 0.. 0 3.. . Aug.30 . . . . . . . . . . . . . . .. 94 90 92 4.. 50.. 44.. . 0M........ Aug.31 . . . . . . . . . . . . . . .. 93 87 90 4.. 40.. 34.. . 00...... . Sept. 1 . . . . . . . . . . . . . .. 95 87 91 3.. 40.. 33.. . 00........ Sept.2 . . . . . . . . . . . . . .. 90 78 84 3.. 32.. 03.. . 00...... . Sept.3 . . . . . . . . . . . . . .. 87 77 82 4.. 30.. 54.. . OOMMM . Sept.4 . . . . . . . . . . . . . .. 85 80 82.54.. 50.. 04.. . 0000 0.. Sept.5 . . . . . . . . . . . . . .. 87 82 84.55.. 50.. 63.. . 00000.. Sept.6 . . . . . . . . . . . . . .. 89 80 84.5 5.. 5 6.. 3 5.. . 00000.. Septz7 . . . . . . . . . . . . . .. 85 80 82.55.. 45.. 34.. . 00000.. Sept:8 . . . . . . . . . . . . . .. 86 84 85 3.. 42.. 32.. .0000 0M Sept 9 . . . . . . . . . . . . . .. 90 85 87.55.. 44..27...000000 Sept.10 . . . . . . . . . . . . . .. 95 86 90.5 4.. 2 5.. 3 3.. .0 0 7 010 1 Septll . . . . . . . . . . . . . .. 95 87 91 4.. 13.. 33.. .000000 Septl2 . . . . . . . . . . . . . .. 96 87 91.5 1 35.. 2 1.. . 000030 Sept..13...... . . . . . . . . .. -97 80 88.5 4. 2 3. 3 3.. . 0 0 00,3 0 M—-Mated. D—-Died. L-Lost. 62 BULLETIN N0. 308. Table 18—-Rate of Oviposition——Continued D Temperature Pair Number ate Max. Min. Mean 21 24262829 3233 3435 36 37 38394041 4243 1919 Sept 14 . . . . . . . . . . . .. 92 77 84. 3 2 3 3 3 0 0 0 0 3 .. Sept 15 . . . . . . . . . . . .. 90 8O 85 3 1 2 2 2 0 0 4 0 2l0....... .. Sept 16 . . . . . . . . . . . .. 89 82 85. 643330000O0....... .. Sept 17 . . . . . . . . . . . .. 87 83 85 O 5 3 410 0 0 0 6 Sept 18 . . . . . . . . . . . . .. 89 83 86 4 3 3 2 2 0 0 0 0 3 Sept 19 . . . . . . . . . . . .. 9O 85 87.5 5 2 3 3 3 O 0 0 0 0 Sept 2O . . . . . . . . . . . .. 91 86 88.5 3 4 3 3 3 0 0 O 0 5 Sept 21 . . . . . . . . . . . .. 89 86 87.5 3 4 2 2 2 0 0 0 0 5 Sept 22 . . . . . . . . . . . .. 89 87 88 2 2 3 1 1 0 0 0 0 0 Sept23 . . . . . . . . . . . .. 84 76 80 20220000300.......... Sept.24 . . . . . . . . . . . . ~. 77 75 76 2 5 1 0 3 310 0 1 5 Sept.25 . . . . . . . . . . . .. 85 74 79.5 0 4 3 4 0 0 2D 0 2 Sept.26 . . . . . . . . . . . .. 81 75 78 5 4 3 3 2 0 0.. 0 2 Sept.27 . . . . . . . . . . . .. 83 75 79 2 5 3 0 2 1 6. 3 5 Sept.28 . . . . . . . . . . . .. 89 81 85 1 5 2 0 1 1 5. 3 5 Sept.29 . . . . . . . . . . . .. 92 83 87.5 3 3 5 7 3 O 4. 2 5 Sept.30 . . . . . . . . . . . .. 96 8O 88 5 2 3 2 3 3 3. 1 5 Oct. 1 . . . . . . . . . . . . .. 94 8O 87 3 6 5 5 3 0 0. 0 3 5.......... Oct. 2 . . . . . . . . . . . . .. 94 83 88.5 2 5 3 5 5 4 6. 0 0 Oct 3. . . . . . . . . . . . .. 89 82 85.5 1 3 0 4 1 2 0.. 0 8 0MMM.... Oct 4 . . . . . . . . . . . . .. 92 83 87.5 0 4 6 413 4.. 0 4 7 2 1 2.... Oct. 5 . . . . . . . . . . . . .. 93 82 87.5 0 3 5 3 1 3 4.. 0 3 6 1 0 1.. Oct. 6 . . . . . . . . . . . . .. 91 82 86.50304230..D32000...... Oct. 7 . . . . . . . . . . . . .. 85 8O 82.50250308.... O3523...... Oct. 8 . . . . . . . . . . . . .. 9O 82 86 O22D200.. 20244MMM Oct.9 . . . . . . . . . . . . .. 90 84 87 347..589.. 55733205 Oct.1O . . . . . . . . . . . . .. 91 86 88.5 3 4 6 4 1 5.. 3 3 5 5 6 5 3 3 Oct.11 . . . . . . . . . . . . .. 88 78 83 123. 203.. 31424212 Oct12 . . . . . . . . . . . . .. 79 75 77 123. 103.. 20313102 Oct13 . . . . . . . . . . . . .. 76 74 75 332. 302.. 42323203 Oct 14 . . . . . . . . . . . . .. 75 74 74.5222. 202.. 31312202 Oct15 . . . . . . . . . . . . .. 78 74 76 103. 301.. 30244003 Oct16 . . . . . . . . . . . . .. 81 79 80 O23..303.. O02233D1 Oct 17 . . . . . . . . . . . . .. 81 73 77 122.. 202-.. 2D0000.. 1 Oct.18 . . . . . . . . . . . . .. 73 69 71 003.. 202.. 3.. 3232.. 2 Oct.19 . . . . . . . . . . . . .. 75 70 72.5 0 0 2..10 1.. 2. 2 1 2 1.. 1 0ct.20 . . . . . . . . . . . . .. 75 72 73.5 3 0D.. 0 0 1.. 3. 4 1 3 0. 3 Oct.21 . . . . . . . . . . . . .. 82 75 78.5 1 0.... 002.. 3. 2250.. 4 Oct.22 . . . . . . . . . . . . .. 84 79 81.5 3 0. 8 1 2.. 4. 5433.. 6 M-—Mated D-—-Died. L—-L0st. THE SWEET Potrmo WEEVIL. Table 18——Rate of Oviposition-Continued 63 D t Temperature Pair Number M», ae Max. Min. Mean 21 242932333638394041 43 444546474849 1919 Oct 23 . . . . . . . . . . . . .. 87 83 85 0 0 9 1 4 4 4 5 6 3 Oct.24 . . . . . . . . . . . . .. 9O 84 87 0 O 4 0 1 3 3D 4 4 Oct.25 . . . . . . . . . . . . .. 90 85 87.5 4 0 5 1 6 5 3.. 5 5 Oct.26 . . . . . . . . . . . . .. 89 86 87.5 3 0 5 0 6 5 2.. 4 5 Oct.27 . . . . . . . . . . . . .. 88 86 87 2 0 4 O 4 4 3.. 4 6 Oct.28 . . . . . . . . . . . . .. 9O 8O 85 0 0 1 4 0 3 0.. 2 1 Oct.29 . . . . . . . . . . . . .. 80 77 78.5 1 010 2 2 O.. 2 5 Oct.30 . . . . . . . . . . . . .. 79 73 76 10 3 0 4 3 2.. 3 5 O .31 . . . . . . . . . . . . .. 84 79 81.52040251.. 442........... Nov. 1 . . . . . . . . . . . .. 87 75 81 2 0 312 O 0.. 1 2 Nov 2 . . . . . . . . . . . . .. 79 73 76 2 0 2 1 1 O O..1 2 Nov 3 . . . . . . . . . . . . .. 74 73 73.5002001 0.. O03........... Nov 4 . . . . . . . . . . . . .. 79 73 76 2 0 2 0 3 4 0.. O 0 Nov 5 . . . . . . . . . . . . .. ‘78 72 75 1 0 3 O 3 2 1.. O 0 Nov 6 . . . . . . . . . . . .. 82 74 78 1 0 3 0 2 1 0.. 0 0 Nov 7 . . . . . . . . . . . .. 84 76 80 O 0 2 C 3 4 0.. 0 6 Nov 8 . . . . . . . . . . . . .. 88 76 82. 104C430..D55............ Nov 9 . . . . . . . . . . . . .. 94 80 87 104C420.... Nov 10 . . . . . . . . . . . .. 92 81 86.5 0 0 2 0 3 3 0.. 2 Nov 11 . . . . . . . . . . . . .. 84 76 8O “OD 3 0 4 2 O.. O . Nov 12 . . . . . . . . . . . .. 81 74 77.5 7.. 2 O 3 2 0.. 0 . Nov.13 . . . . . . . . . . . . .. 82 75 78.5 1. 2 0 0 3 0.. 5 Nov.14 . . . . . . . . . . . . .. 82 66 74 2. 3 0 0 3 O.. 0 Nov.15 . . . . . . . . . . . . .. 83 76 79.5 0. 3 0 4 3 0.. N0v.16 . . . . . . . . . . . .. 79 75 77 0. 2 O 3 2 O.. Nov.17 . . . . . . . . . . . . .. 82 75 78.5 4. 3 0 2 3 4.. 2 Nov.18 . . . . . . . . . . . . .. 83 76 79.5 0. 3 O 0 2 1.. 0. N0v.19 . . . . . . . . . . . . .. 83 79 81 0.. 3 O2 3 O.. 0. Nov.2O . . . . . . . . . . . . .. 80 75 77.5 0.. 5 0 3 2 0.. 0. N0v.21 . . . . . . . . . . . . .. 82 77 79.5 4.. 3 0 3 3 0.. 0. Nov.22 . . . . . . . . . . . . .. 84 78 81 0.. 413 3 2.. 0. Nov 23 . . . . . . . . . . . . .. 86 78 82 0.. 3 1 2 2 1.. 0.... Nov 24 . . . . . . . . . . . .. 87 83 85 0.. 3 0 3 4 3.. 0..MMM OMM» Nov.25 . . . . . . . . . . . .. 88 82 85 0.. 50340.. 0.. 000000 N0v26 . . . . . . . . . . . .. 89 81 85 0.. 00110.. O.. 0O0000~ N0v27 . . . . . . . . . . . . .. 8O 73 76.50.. O01 10.. O.. 131 681 N0v28 . . . . . . . . . . . . .. 73 69 71 0..00110.. 0.. 121311 Nov.29 . . . . . . . . . . . . .. 79 70 74.5 O.. 4 0 1 1 0.. 0..1 1 0 2 1 1 Nov3O . . . . . . . . . . . . .. 79 66 72.50.. 40110.. O.. 402212 M—Mated. D-—Died. L-Lost 64 BULLETIK N0. 308. Table 18——Rate of Oviposition—Continued D t Temperature Pair Number ae + . Max. Min. Mean 21293233363841444546474849 1919 Decl . . . . . . . . . . . . . . . . . . . . . . .. 72 68 70 0101200040120 Dec2 . . . . . . . . . . . . . . . . . . . . . . .. 76 70 73 0101000100001 Dec3 . . . . . . . . . . . . . . . . . . . . . . .. 71 64 67.50100200223224 Dec4 . . . . . . . . . . . . . . . . . . . . . . .. 78 65 71.50200200323233 Dec5 . . . . . . . . . . . . . . . . . . . . . . .. 79 70 74.50200200322122 Dec6 . . . . . . . . . . . . . . . . . . . . . . .. 88 76 82 0605310552156 Dec7 . . . . . . . . . . . . . . . . . . . . . . .. 94 83 88.50504200552145 Dec8 . . . . . . . . . . . . . . . . . . . . . . .. 87 74 80.5D304300697354 Dec9 . . . . . . . . . . . . . . . . . . . . . . .. 91 75 83 ..203000230020 Dec10 . . . . . . . . . . . . . . . . . . . . . . .. 79 72 75.5 201400022033 Dec.11 . . . . . . . . . . . . . . . . . . . . . . .. 80 68 74 . 201300143200 Dec.12 . . . . . . . . . . . . . . . . . . . . . . .. 87 72 79.5. 203200333070 Dec.13 . . . . . . . . . . . . . . . . . . . . . . .. 81 60 70.5. 001000010114 Dec.14 . . . . . . . . . . . . . . . . . . . . . . .. 73 66 69.5. 000000000104 Dec.15 . . . . . . . . . . . . . . . . . . . . . . .. 65 63 64.300200023020 Dec.16 . . . . . . . . . . . . . . . . . . . . . . .. 75 66 70.5.. 200000422033 Dec.17 . . . . . . . . . . . . . . . . . . . . . . .. 80 75 77.5..300003442040 Dec.18 . . . . . . . . . . . . . . . . . . . . . . .. 89 74 81.5.. 303000444600 Dec.19 . . . . . . . . . . . . . . . . . . . . . . .. 93 77 85 .. 3045000522910 Dec.20 . . . . . . . . . . . . . . . . . . . . . . .. 93 77 85 .. 403300653626 Dec.21 . . . . . . . . . . . . . . . . . . . . . . .. 86 73 79.5.. 403300652716 Dec.22 . . . . . . . . . . . . . . . . . . . . . . .. 86 74 80 .. 4033D0040334 Dec.23 . . . . . . . . . . . . . . . . . . . . . . .. 86 73 79.5.. 401 1.. 0320330 Dec.24 . . . . . . . . . . . . . . . . . . . . . . .. 84 75 79.5..0011. 0320331 Dec.25 . . . . . . . . . . . . . . . . . . . . . . .. 82 66 74 .. 1322. 0321331 Dec.26 . . . . . . . . . . . . . . . . . . . . . . .. 77 56 66.5..1 012. 0 0 2 0 2 1 1 Dec.27 . . . . . . . . . . . . . . . . . . . . . . .. 79 72 75.5..1022. 0130210 Dec.28 . . . . . . . . . . . . . . . . . . . . . . .. 81 78 79.5.. 0024. 01,301 10 Dec.29 . . . . . . . . . . . . . . . . . . . . . . .. 83 80 81.5.. 3 043. 022 0443 Dec.30 . . . . . . . . . . . . . . . . . . . . . . .. 84 81 82.5.. 4033.. 0430023 Dec.31 . . . . “i926 . . . . . . . . . . . . .. 86 83 84.5.. 2 0 2 2.. 0 2 3 0 2 0 3 Jan. 1 . . . . . . . . . . . . . . . . . . . . . . .. 88 81 84.5..2021..0330323 Jan.2 . . . . . . . . . . . . . . . . . . . . . . .. 81 77 79 ..2021..0330323 Jan.3 . . . . . . . . . . . . . . . . . . . . . . .. 78 74 76.2021..0440223 Ja.n.4 . . . . . . . . . . . . . . . . . . . . . . .. 80 76 78 . 2122..0440223 Jan.5 . . . . . . . . . . . . . . . . . . . . . . .. 80 72 76.0001..0120133 Jan.6 . . . . . . . . . . . . . . . . . . . . . . .. 75 71 73 . 0013..0000110 Jan.7 . . . . . . . . . . . . . . . . . . . . . . .. 78 73 75.5. 0010..0000230 Jan.8 . . . . . . . . . . . . . . . . . . . . . . .. 80 74 77 . 0022..0030200 M—M ate d. D——Died. L—-Lost. 65 THE SWEET POTATO WEEVIL. Table 18—-Rate of Oviposition——(jontinued Pair Number u m u n u H . . n U HM000004100300411312102202002 H . . . . H . H . . .M000000000000522333223302000 . m . . . . . . . . .MO000OO0002006O0642221103110 0223290044544121213222555344242223300110 132210633444032214033343365320033300000 11000050055004.622122321135424430022233140113 201000000000000000001022000000000000000 0004330007042322232212552330D . . . . . . . . . . 111000000000000000000000000000000000000 9-114433001000000OOOOOOOOOOOOOD . . . . . . . . _ 1121.445w554420322111132O0660o314210210000D 311000000000000000000000000000010000000 001433343332022210222343443332222111000 Temperature Mean 29 32 33 36 41 44 45 46 47 48 49 5O 51 52 53 5555 5 5555 55 5555 466700447543943510114 00007777777777000000000000007 555 5 Min. Max. Date - . ¢ . - . . - . . . . . . - . . . - . . . . . . . . . . . . . . . . . . . . - Q . » . . . . - - . - . . - - . . . . . . . . . . . . . . - - . - . - . . M-——-Mated. D—-—Died. L—L0st. 66 I BULLETIN X0. 308. Table 18—Rate of Ovip0sition—Continued Temperature Pair Number Max. Min. Mean 29 32 41 45 46 47 48 49 50 51 U‘ l0 53 w w Q Q N Q Q Q Q m Q o m m Q H p . . W . U1UYU1C” UTUT UYUT UTUYUT UTU‘ UTU\UYU'\CJTU\U\UTU\U\UT U?‘ IUooooo~»~wm-oo~owoooowowoowww~wm I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I UQQ@ IUcooooooooooooooooooooooooooooo §Uooo §Uo ooommooooooooooo-ooooo~oooo~owo-~w-o OOCJOOOOOOOOOOOOOOOOOQOOCOOOOOOOOOMNOQOOO OOOOUOOOOOOOOOOOOOOOQOOOOOOOOOOOOOOQOOOO OOOOOOOOOCOOOOOOOOOOOOOOOP-‘OOOOOOWHWIOHP-“M lOshvikwUJOOflOvkbObJlOHLOCOIOOOOOOP-‘Hr-“OflHOIOIQHNIQMBDMO CDMJAWOOOOHLJORZMPvhlOlxiwv-‘UOOOWOOI-‘MI-‘NOOO[OMIOMOOFH-lw OMWOUYOOOOPOOWNNrPoOOOOOl-lQOOOOfiwOfiOOfifiOCN M-Mated. D—Died. L—Lost. THE SWEET POTATO WEEVIL. Table 18-—-Rate 0f Ovipositi0n—-Continued . 67 Temperature Pair Number Date Max. Min. Mean 45 46 47 49 ' 5O ,52 53 1920 - March 27 . . . . . . . . . . . . . . . . . . . . . . . 85 79 82 O O O 0 3 2 1 March 28 . . . . . . . . . . . . . . . . . . . . . . . 84 76 80 0 O O 0 2 1 0 March 29 . . . . . . . . . . . . . . . . . . . . . . . 83 77 8O 3 O O 8 1 O O March 30 . . . . . . . . . . . . . . . . . . . . . . . 82 76 79 1 O 1 1 4 1 2 March 31 . . . . . . . . . . . . . . . . . . . . . . . 82 75 78 .5 O 0 0 O 3 1 1 pril 1 . . . . . . . . . . . . . . . . . . . . . . . . 84 77 80.5 0 0 O 2 1 1 2 April 2 . . . . . . . . . . . . . . . . . . . . . . . . . 87 74 80.5 O 0 0 2 0 O 2 April 3 . . . . . . . . . . . . . . . . . . . . . . . . 79 73 76 O 0 0 1 1 O 2 April 4 . . . . . . . . . . . . . . . . . . . . . . . . 81 73 77 O 0 O 2 1 O 1 April 5 . . . . . . . . . . . . . . . . . . . . . . . . . 72 68 70 0 0 0 2 1 0 2 April 6 . . . . . . . . . . . . . . . . . . . . . . . . . 75 71 73 0 0 O 1 1 0 2 April 7 . . . . . . . . . . . . . . . . . . . . . . . . . 83 74 78.5 0 0 0 1 1 0 2 April 8 . . . . . . . . . . . . . . . . . . . . . . . . . 83 78 80.5 O 0 0 2 3 1 4 April 9 . . . . . . . . . . . . . . . . . . . . . . . . . 85 78 81 .5 0 0 0 2 3 1 2 April 1O . . . . . . . . . . . . . . . . . . . . . . . . . 85 81 83 0 0 O 1 3 1 2 April 11 . . . . . . . . . . . . . . . . . . . . . . . . . 83 81 82 O 0 0 1 3 0 4 April 12 . . . . . . . . . . . . . . . . . . . . . . . . 85 77 81 O O O 2 2 1 2 April 13 . . . . . . . . . . . . . . . . . . . . . . . . . 83 75 79 0 O O 1 2 1 3 April 14 . . . . . . . . . . . . . . . . . . . . . . . . . 79 73 76 O O O 1 2 1 2 April 15 . . . . . . . . . . . . . . . . . . . . . . . . 81 78 79.5 0 O 0 1 2 0 3 pril 1 . . . . . . . . . . . . . . . . . . . . . . .. 84 79 81.5 O O 0 1 2 _O 4 April 17 . . . . . . . . . . . . . . . . . . . . . . . . . 94 83 88 .5 0 0 0 1 2 0 2 April 18 . . . . . . . . . . . . . . . . . . . . . . . . 9O 85 87.5 0 0 O 2 2 0 2 April 19 . . . . . . . . . . . . . . . . . . . . . . . . 89 83 86 0 O 0 5 2 0 2 April 20 . . . . . . . . . . . . . . . . . . . . . . . . 88 82 85 0 0 0 1 2 0 2 April 21 . . . . , . . . . . . . . . . . . . . . . . . . . 86 80 83 0 0 O 1 2 0 3 April 22 _ . . . . . . . . . . . . . . . . . . . . . . . . 90 82 86 O 0 0 1 2 O 2 April Z3 . . . . . . . . . . . . . . . . . . . . . . . . 89 82 485.5 O 0 0 1 2 O 2 April 24 . . . . . . . . . . . . . . . . . . . . . . . . . 85 82 83.5 0 0 0 1 2 0 2 April 25 . . . . . . . . . . . . . . . . . . . . . . . . . 85 80 82.5 0 O 0 1 2 D 2 April 26 . . . . . . . . . . . . . . . . . . . . . . . . 86 80 83 0 0 0 1 2 . . . . 1 April 27 . . . . . . . . . . . . . . . . . . . . . . . . . 80 73 76.5 0 0 0 0 O O April 28 . . . . . . . . . . . . . . . . . . . . . . . . 76 73 74.5 0 0 0 0 0 O April 29 . . . . . . . . . . . . . . . . . . . . . . . . . 82 76 79 0 O O 0 O O April 3O . . . . . . . . . . . . . . . . . . . . . . . . 86 79 82.5 O O 0 0 0 O ay . . . . . . . . . . . . . . . . . . . . . . . . . 87 82 84.5 O 0 O 0 0 O May 2 . . . . . . . . . . . . . . . . . . . . . . . . . 9O 84 87 0 0 O 0 0 O lVIay 3 . . . . . . . . . . . . . . . . . . . . . . . . . 91 87 89 0 O 0 0 0 0 May 4 . . . . . . . . . . . . . . . . . . . . . . . . . 94 87 90.5 O 0 O O 0 O M—-Mated. D-—Died. L——Lost 68 BULLETIN N0. 30S. Table 18—-Rate of Oviposition-Continued Temperature Pair Number Date Max. Min. Mean 45 46 47 49 5O 53 1920 May 5 . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 93 86 89 5 0 0 0 0 0 0 May 6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92 86 89 D O O O 0 0 May 7 . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 93 86 89 5 O O 0 O 0 May 8 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92 86 89 O O O 0 O May 9 . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 93 86 89 5 0 0 0 0 0 May 10 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92 86 89 _ 0 0 0 0 0 May 11 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90 86 88 0 0 0 0 0 May 12 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91 87 89 0 O O 0 0 May 13 . . . . . . . . i . . ..’. . . . . . . . . . . . . . .. 93 88 9O 5 O O O O O May 14 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96 87 91 5 0 0 0 0 0 May 15 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87 79 83 0 0 O 0 0 May 16 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84 80 82 O 0 0 O 0 May 17 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81 78 79 0 0 0 0 0 May 18 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81 75 78 0 0 0 0 0 May 19 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85 8O 82 O O O O O May 20 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90 84 87 0 0 0 0 0 May 21 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9O 86 88 O O O O O ay 22 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92 87 89 5 O O O O O May 23 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92 87 89 5 0 0 O 0 0 May 24 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93 89 91 0 0 0 0 0 May 25 . . . . . . . . . . . . . . . . . , , . . . . . . . . . . 93 87 90 0 O 0 0 0 May 26 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94 9O 92 O O O O O May 27 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97 9O 93 5 0 0 0 0 0 May 28 . . . . . . . . . . . . . . . . . . , . . . . . . . . . . 95 87 91 O O O O O May 29 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92 86 89 O O O O O May 3O . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94 86 9O O O O O O ay 31 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94 92 93 0 0 0 0 0 June . . . . . . . . . . . . . . . . . , . . . . . . . . . . . 92 87 89 5 0 0 0 O 0 June 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87 81 84 O O O O O June 3 . . . . . . . . . . . . . . . l . . . . . . . . . . . .. 93 86 89 5 0 0 O 0 0 June 4 . . . . . . . . . . . . . . . . l . . . . . . . . . . .. 94 87 90 5 0 0 0 O 0 June 5 . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 95 86 9O 5 O O O O O June 6 . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 93 84 88 5 O O O 0 O June 7 . . . . . . . . . . . l . . . . . . . . . . . . . . . . . 93 87 90 0 0 O D 0 June 8 . . . . . . . . . A . . . . . . . . . . . . . l . . . .. 93 85 89 0 O 0 . O June . . . . . l . . . . . . . . . . . i . . . . . . . . . . . 92 85 88 5 O 0 O . D June 1O . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 92 83 87 5 O O D . Junell . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 93 88 905 O O . June 12 . . . . . . . . . . . . . . . . . . . . . . . l . . . . . 92 89 9O 5 0 0 . June 13 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93 86 89 5 O O . June 14 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96 9O 93 O O . June 15 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94 85 89 5 O O . June 16 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97 91 94 0 D . June 17 . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 95 89 92 0 .... . June 18 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90 84 87 0 June 19 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89 81 85 0 June 20 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87 81 84 0 June 21 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92 88 9O O June 22 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95 89 92 D M——M ated. D—~Died. L——-L0st . Variations in temperature have a direct influence upon the rate of oviposition. When the mean average temperature falls below 70 de- grees F. the rate at which eggs are deposited begins to decline, and egg deposition may cease entirely below 6O degrees F. The optimum mean temperature for the maximum rate of oviposition ranges from 78 to 95 degrees F. The results given of the winter months are not comparable to the natural conditions, but rather approach the maximum figures. All observations made during the warm season, however, will nearly approxi- mate the natural occurrence of the rate of oviposition, since these observations were made in an open laboratory where conditions close to the normal prevailed. 69 THE SWEET POTATO WEEVIL. .2003 30175.0: T. om §~ - - ' . - . - - - . .....-.--.-.---.i.hoZ mh v E ww mv mh wm hm mvw . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ISQEQC . mm. aw mH 5mw . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Ilgwnawauww 22 mm mm B... 8 mv wv hv wv mv vv mv N? flv ov mm... w». hm 3 m? 53E BQQ dfiiwuoafiou. uvscmwsowvlcnmwwwonmklmv we 3mm Ho hhwiEsmrlmfi vEwH . .. .2 o.hh . . . . . IIJQBSZ n. i . - ¢ . . . - . . ...vh w .hm Tmh . . . . . . . . ...>.~asnww 32 . .ow m Hh méh . . . . . . ....~vnEoooQ .19» v . .Nw wm 05h . . . . . .....$nEv>oZ mm. S"... . .oa mm No av fiv mvw . . . . . . . . . ...~ono~oO .2? w - . . . . . . . . . . . . . . . . . . - - - - - - . - . - N . . . . . . . N . . . . . . . . - - h a u n . - . . ~ . - . . 1 . . . . . . . . . . ALI m . . - - ¢ . . . . . - - - ¢ . . mw hw woflmv hm .mv. .h Nhw ...........~...oc:w . . m 2 mm m: mw mm . m2 wv . . Nw . . 3 . hvw . . . . . . . . . . . S32 11...? mm ow vm m In ow $18 .:2.;$$. 5 1% . . . . . . . . . . . . .._Ca< .....~mh E hfi 5w 3 fiwmmfihlmmwmifimmmlwvwh v.ow . . . . . . . . IIAQENE . . mv. av mm hm .2 m... mv 3 8 3 “a mm ov 3 m mm hm w.wh . . . . . . . . . shfiznnam . . . . mm hv m mm vv ow wm $ 3 mh 3 mh m... Ma S av Q fidh . . . . . . ...wr.ww:§a€ . 3 hm mm 91. om mm mm hm mv wv hm E w. fiw . . . . . . wrnflnivuvm 3* mm mm 3* 3* mm mm h? mm m? vm mm mm _m om 2 wH hH m: m? 3 2 mfi C 2 m w h o m. v m m fi cs3: BQQ .Q.~5aduQQEQ.H. zofimmoafvO mo 3am we bdEEn-W 2 03.9w BULLETIN N0. 308. p5 W? MM 0W WW OW WW QM OW om OW WW OW ~m>w NW .0 wm *1 mm mm om Wm ¢N u-ln n._ WW on 0N NWYTWKQFQ 0Q _. __ 0>15“, .53 > New infestation found in George County, Mississippi. }= , G. M. 1918. Sweet Potato Weevil. Trop. Agriculturist, v. 7 51, no. 3, p. 1'76. 1 pl. Notes on life history and remedies given. shaw, Samuel. 1885. List of Coleoptera of America North of Mexico. Amer. Ent. Soc., p. 145. Listed. 71 W. E. 1918. Ala. Col. Sta. Rept. 30, p. 22. n: W. E. 191.8. Sweet Potato Root Borer. Ala. Col. Sta. Cir. F 37, pp. 3-8. 1 pl. Popular discussion with control measures. ii Quarantine rules and regulations given. ds, W. E. 1919. Report of Entomologist. Ala. C01. Sta. Rept. a‘ 31. Carbon bisulphide fumes failed to kill all stages of the sweet potato weevil. g ids, W. E. 1920. Report of Entomologist. Ala. Col. Sta. Cir. 43. Z Control of weevil in Grand Bay region discussed. . L ard, L. O. 1918. Report of the Entomogolist, U. S. D. A., p. 9. Z ard, L. O. 1919. Report of the Entomologist, U. S. D. A., p. 9. , rd, L. O. 1920.‘ Report of the Entomologist, U. S. D. A., pp. <,12-3. Progress report of eradication work in Florida, Georgia and f Mississippi. _. lard, L. O. 1921. Report of the Entomologist, U. S. D. A., p. 10. l. Summary of results of eradication in Florida, Georgia and Alabama. 84 BULLETIN N0. 308. Hutson, J. C. 1917. Insect Notes. Agr. News, Barbados, v. 16, no. 388,, p. 74. Records Cflas formicarius from Barbados, and states that it is not known to be present in the Lesser Antilles. Hutson, J. C. 1917. Insect Notes. L00. cit. Of. Rev. Appl. Ent. Sers. A, v. 5, p. 479. Correction note made on distribution. Weevil does not occur in Barbados. 1917. The Sweet Potato Root Weevil. Agr. News, Barbados, v. 16, no. 405, p. 347. Reference to a public notice issued by the Florida State Plant Board concerning quarantine measures against the sweet potato weevil. Hutson, J. C. 1918. The Sweet Potato Root Weevil. Agr. News, Barbados, v. 17, no. 412, pp. 42-3. 1 fig. Suggestions for con- trol, based upon Florida State Plant Board recommendations. Hutson, J. C. 1920. Report of the Entomologist. Ceylon Dept. Agr. Administr. Repts. for 1919. Reports the weevil attacking sweet potatoes. Hyslop, J. A. 1921. Summary of Insect Conditions Throughout the United States During 1.921. U. S. D. A. Bull. 1103, pp. 34-7. 2 figs. Summary of the insect in the Gulf States, and map showing distribution. Jones, T. H. 1915. Insects Affecting Vegetable Crops in Porto Rico. U. S. D. A. Bull. 192, pp. 6, 11. Observed in tuberous roots of wild convolvulaceous plant. Kingman, F. C. & Doryland, E. D‘. 1917. Important Root Crops oi the Philippines. Philip. Agr. Rev., v. 10, no. 4, pp. 346-7. 1 pl. Notes on injury. Early harvest and crop rotation suggested for control. Labaam, D. & Imhofi, L. 1838. Singulorum Generum Curculionidum Icones I, no. 25. O. tiarcipennis. Lacordaire, Th. 1863. Genera des Coleopteres. Tom. VI, p. 529. Le Conte, J. L. & Horn, G. H. 1883. Classification of the Coleoptera of North America. Smithsonian Misc. Coll., p. 507. Occurrence in Louisiana and Florida. Lefroy, H. M. 1910. Life Histories of Indian Insects, Coleoptera I. Mem. Dept. Agr. India, Ent. Sers., v. 2, no. S, pp. 155-9. 1 pl. Origin, description, life history notes and preventive measures. Leng, C. W. 1920. Catalogue of Coleoptera of America North oi Mexico, p. 309. Listed. Distribution. Lyle, Clay. 1921. Summary of State Plant Board Work Previous tc 1921. Miss. St. Pl. Bd. Quar. Bulk, v. 1, no. 1, pp. 5, 6-7. Sum- mary of results obtained in eradication work. Lyne, W. H. 1921. A Talk on Insects Imported from the Orient. Proc. Ent. Soc. Brit. Col., Ec. Sers., nos. 13 & 15. Noted in list of pests infesting stored products. Maskew, Frederick. 1913. Sweet Potato Weevil. Calif. Dept. Agr Mthly. Bull., v. 2, no. 5, pp. 535-7. 2 figs. Notes on distribution nature of injury and description are given. Mische, William. 1880. Rare Beetle Injurious to Sweet Potato Roots in Louisiana. Amer. Ent., v. 3 (n. s., v. 1), p. 297. Notes or ravages of the sweet potato weevil. THE SWEET POTATO WEEVIL. 85 I Montgomery, J. H. 1920. Notes from the Quarantine Department. ' Fla. St. Pl. Bd. Quar. Bull., v. 5, no. 1, pp. 3-4. Account of new V. outbreak of Weevil in Florida. 1 More, J. D. 1921. La Vaquita o Piche de la Batata. P. R. Ins. *- Expt. Sta. Cir. 34, pp. 6. 1 pl. Popular account of sweet potato weevil in Porto Rico. Morgan, H. A. 1894. Sweet Potato Borer. La. Agr. Expt. Sta. Bull. 28, 2 sers., pp. 997-1000. 1 fig. Describes ravages in Louisiana. Mote, D. C. 1921. The Sweet Potato Weevil. 12th and 13th Ann. ' Rept. Ariz.‘ Comm. Agr. and Hort., pp. 57-9. 1 fig. Brief popular account. jNewell, W. 1917. The Sweet Potato Root Borer in Florida. Fla. a St. Pl. Bd. Quar. Bull., v. 1, no. 2, p. 53. Distribution in Florida. 1Newell, W. 1917. Sweet Potato Root Weevil. Fla. St. Pl. Bd. Quar. ” Bull., v. 2, no. 1, pp. 81-100. 2 figs. History, distribution, life history, remedies and quarantine regulations are discussed. yNewell, W. 1918. Sweet Potato Regulations. Fla. St. Pl. Bd. Quar. - Bull., v. 2, no. 3, pp. 157-8. Calls attention to weevil quarantine ~1- regulations enacted by other Southern States. Newell, W. 1919. Report of the Plant Commissioner for the Biennium Ending April, 1918, and Supplemental Reports. Fla. St. Pl. Bd. control measures discussed. lNewell, W. 1920. Fla. St. Pl. Bd. Quar. Bull., v. 4, no. 4, p. 120. Note concerning ravages of weevil in Jamaica. INeWell, W. 1921. Report of the Plant Commissioner for the Biennium 5 Ending April, 1920, and Supplemental Reports. Fla. St. Pl. Bd. Quar. Bull., v. 5, no. 2, pp. 46-117. 2 figs. Summary of results f, of eradication work and inspections. liNewell, W. & Berger, E. W. 1922. Insects Injurious to the Principal " Crops of the South. Fla. St. Pl. Bd. Quar. Bull., v. 6, no. 4, pp. 102-3. Brief account of insect. Newell, W. & Rosenfeld, A. H. 1908. A Brief Summary of the More Important Injurious Insects of Louisiana. J our. Ec. Ent., v. 1, no. 5' 2, p. 153. Mention species. ewell, W. & Rosenfeld, A. H. 1909. The Sweet Potato Weevil. La. l St. Cr. Pest Comm. Cir. 27, pp. 104-6. 1 fig. Brief account of life history. ewstead, R. 1910. Some Insect Pests Affecting Cultivated Plants '5 in the West Indies. J our. Roy. Hort. Soc., (London), v. 36, no. 1, ' ietner, J. 1857. N otizen uber Cy/Zas turcipenrzis und andere Schad- i liche Insectcn von Ceylon. Stettiner Ento. Zeitung, v. 18, pp. 36- 41. Describes occurrence, nature and extent of injury to SWGvlJ potatoes in Ceylon. _’Kane, W. C. 1912. Injurious Insects, pp. 117, 383. Brief popular i account. livier, G. A. 1807. Ent. Hist. Natur. Insect, v. 5, p. 84, bis, p. 446; ‘ Tab. 2, F. 19. Technical. description. rton, W. A. & Chittenden, F. H. 1917. Control of Diseases and ‘ Insect Enemies of the Home Vegetable Garden. U. S. Farm. Bull. 856, pp. 63-4. 2 figs. Brief discussion, including remedies. Quar. Bull., v. 3, no. 2, pp. 65-71. 1 fig. Habits, food plants, and. 86 BULLETIN N0. 308. _ Rosewell, O. W. 1920. Two Rhynchophora Found Feeding in Sweet I Sanderson, E. D. 1899. Sweet Potato Insects. Md. Agr. Expt. Sta. = Patterson, W. H. 1914. Report of the Entomologist. Gold Dept. Agr. Rept. for 1.913. Sweet potatoes at Aburi seriously " - jured by Oylas formvicarius. Pierce, W. D. 1917. Sweet Potato Weevil. Man. Danger. Inset pp. =6, 209. Description, biology, and distribution. A. Pierce, W. D. 1918. Weevils Which Aifect Sweet Potato Tubers. I} S. D. A. Jour. Agr. Res., v. 12, no. 9, pp. 604-5. 4 pls. Techni f, description and key for separating species of Cylas. . A Pillai, R. M. 1921. Short Notes on the Insect Pests of Crops -' Travancore. Travancore Dept. Agr. Trivandrum, 1921. Brief a ' count of insect attacking sweet potatoes. Price, R. H. 1895. Tex. Agr. Expt. Sta. Bull. 36, pp. 624-5. 1 ;..s.-...wia-q_mmimau‘- -’ ‘ ~