effective than dieldrin but more effective than 

 toxaphene; and six were slightly more effective 

 than or equal to toxaphene. 



36. Chadbourne, D. S. Some histological 

 aspects of the boll weevil. Ent. Soc. Amer. 

 Ann. 54 : 788-792. 1961. 



Histological studies of microtome sections of 

 fixed specimens of the boll weevil revealed the 

 general structure of the alimentary canal, 

 stomodaeum, mesenteron, proctodaeum, Mal- 

 pighian tubules, male reproductive organs, fat 

 bodies, oenocytes, labial glands, muscle, and 

 attachment to body wall. Detailed drawings 

 are given. 



37. Clark, E. W., Richmond, C. A., and 

 McGough, J. M. Artificial media and rearing 

 techniques for the pink bollworm. Jour. Econ. 

 Ent. 54: 4-9. 1961. 



Pink bollworms, boll weevils, and phorid flies 

 were raised on an artificial diet of cottonseed 

 meal combined with other constituents. Growth 

 of the boll weevil was slow and sporadic. A 

 peanut-flour diet was tested on the pink boll- 

 worm. Other diets and techniques for handling 

 the eggs and larvae are described. 



38. Cleveland, T. C. A nematode parasite 

 of the boll weevil. Jour. Econ. Ent. 56: 897. 

 1963. 



A nematode, Hexamermis sp., was discovered 

 in the boll weevil while analyses for diapause 

 status were being made. The nematodes, re- 

 covered from boll weevils collected from certain 

 localities near Tallulah, La., during the springs 

 of 1960 and 1961, were 2 to 6 cm. in length and 

 ivory in color. 



39. Cleveland, T. C, and Smith, G. L. 

 Effects of postseason applications of insecti- 

 cides, defoliants, and desiccants on diapausing 

 boll weevils. Jour. Econ. Ent. 57: 527-529. 

 1964. 



In a 3-year field study at Tallulah, La., 

 postseason applications of insecticides, defoli- 

 ants, and desiccants were all effective in re- 

 ducing the number of diapausing boll weevils 

 entering ground trash. Defoliants and desic- 

 cants appeared to cause the greatest reduction 

 in overwintering populations entering winter 

 quarters. Weekly applications of methyl para- 

 thion and Guthion during this period also 

 reduced the overwintering weevil populations 

 to a low level. However, none of the treatments 

 completely eliminated the weevil populations 

 in this series of experiments. 



40. Cole, C. L., and Adkisson, P. L. Daily 

 rhythm in the susceptibility of an insect (boll 

 weevil, Anthonomus grandis, Boh.) to a toxic 

 agent. Science 144: 1148-1149. 1964. 



Adult boll weevils exhibited a daily rhythm 

 in their susceptibility to standardized doses of 

 the insecticide methyl parathion. The mortality 

 produced by the insecticide was intimately re- 



lated to the time of day at which the toxicant 

 was applied. The rhythm appeared to be pho- 

 toperiodically entrained and, regardless of the 

 length of day or "clock time-of-day" of treat- 

 ment, a period of greatest resistance always 

 occurred at dawn and recurred at 6-hour in- 

 tervals throughout the 24-hour cycle. The 

 greatest difference in response occurred in a 

 photoperiod having 10 hours of light per 24- 

 hour cycle. In this photoperiod, the same dose 

 of methyl parathion killed approximately 10 

 percent of the weevils treated at dawn but 

 almost 90 percent of those treated only 3 hours 

 later. 



41. Cole, C. L., and Adkisson, P. L. Cir- 

 cadian rhythm in the susceptibility of an insect 

 to an insecticide. In Jurgen Aschoff, ed., 

 Circadian Clocks. Proceedings of the Feldafing 

 Summer School, 7-18 September, 1964., pp. 

 309-313. 1965. North-Holland Publishing Co. 

 Amsterdam. 



Proof that circadian rhythm is photoperiodi- 

 cally entrained was obtained in experiments 

 with adults kept in continuous light. In weevils 

 so kept there were no significant differences in 

 mortality of those treated at different times of 

 day. An exposure to seven or eight light-dark 

 cycles was necessary to establish rhythm. 



In furthur tests weevils were decapitated 

 and the wound sealed with a small amount of 

 melted paraffin. These and normal adults were 

 exposed to the same photoperiods and the 

 same insecticidal treatment. Decapitated con- 

 trols were maintained. Decapitated weevils 

 behaved as if they were under continuous il- 

 lumination. This indicates that the cephalic 

 region in the insect is involved in the sensi- 

 tivity rhythm. 



42. Cory, R. A., Moye, W. C, and Hall, 

 W. E. Laboratory and field evaluation of 

 SD9129 as an insecticide. Jour. Econ. Ent. 58: 

 658-660. 1965. 



The discovery of a highly toxic metabolite of 

 Bidrin in house flies led to the synthesis of 

 SD9129, a relatively nonvolatile, persistent 

 systemic insecticide. It is highly toxic to many 

 insect pests, especially lepidopterous larvae. It 

 is promising for control of bollworm and boll 

 weevil. 



43. Cowan, C. B., Jr., and Davis, J. W. 

 Control of several late-season cotton pests in 

 field experiments in 1962. Jour. Econ. Ent. 56 : 

 790-793. 1963. 



Stauffer R-1504 in a 1:1 mixture of Guthion 

 plus ethyl Guthion compared favorably in con- 

 trol of the boll weevil with Guthion plus DDT. 

 Monsanto CP-40294 and Bayer 29493 plus 

 DDT were less effective. Zectran and Bayer 

 37344 gave boll weevil control comparable to 

 that obtained with Sevin. Data are given for 

 bollworm, cabbage looper, and desert spider 

 mite. 



