Jan. 12 ,1924 
Effect of Cold Storage on Bean Weevils 
105 
A comparison of Tables IV and V shows that the eggs are more easily 
killed by low temperatures than the more advanced stages. 
SUMMARY 
BRUCHUS OBTECTUS 
Exposure of larvae, pupae, and adults of Bruchus obtectus f infesting 
California pink beans, to 32 0 F. for 56 days or to 36° F. for 66 days gave 
very satisfactory control. Considerably shorter periods of exposure 
rendered the surviving adults incapable of reproduction. 
BRUCHUS QUADRIMACUUATUS 
A temperature of 39 0 F. for 32 days was insufficient to kill all stages 
within black-eye cowpeas. All stages were killed when subjected to 
32 0 F. or colder for 32 days. 
The eggs were killed by four days’ refrigeration at 32 0 or 20° F., but 
a longer time was necessary to kill them at 39 0 . They were more sus¬ 
ceptible to cold than the other stages. 
literature CITED 
(1) Back, E. A., and Duckett, A. B. 
1918. bean and pea weevils. U. S. Dept. Agr. Farmers’ Bui. 983, 24 p., 
24 fig. 
(2) DuvEL, J. W. T. 
1905. cold storage for cowpeas. In U. S. Dept. Agr., Bur. Ent. Bui. 54, 
“ Some miscellaneous results of the work of the Bureau of Entomology/ 
VIII,” p. 49-54, fig. 17, pi. 2-3. 
(3) G ARM AN, H. 
1917. OBSERVATIONS AND EXPERIMENTS ON THE BEAN AND PEA WEEVILS IN 
Kentucky. Ky. Agr. Exp. Sta. Bui. 213, p. 305-333, 8 fig. 
(4) Krall, John A. 
1914. a cowpea weevil (pachymerus chinensis). Okla. Agr. Exp. Sta. 
Circ. 31, 8 p. 
(5) Severin, H. C. 
1919. THE BEAN WEEVIL. S. Dak. Off. State Ent. Circ. 15, 7 p., 2 fig. 
