THE MEXICAN BEAN BEETLE 31 



Conclusions 



Adults. A temperature of 37° kills the beetles in a few hours; 32° is very- 

 unfavorable with high humidity and favorable with low humidity; 27° is 

 suitable for heavy oviposition with humidity of 60 per cent or above and 

 unfavorable with low humidity, but favorable for length of life with all hu- 

 midities used; 22° is favorable with humidities of 40 per cent or above; and 

 17° with 50 per cent humidity is favorable for length of life but is very un- 

 favorable for egg production. 



Eggs. — A temperature of 37° kills the embryos; 32° is very destructive if 

 reached for more than a few hours daily; 27° is suitable with humidities of 

 60 per cent or above and unfavorable with low humidity; 22° is very favor- 

 able with humidities of 60 per cent or above, but less favorable with low hu- 

 midity; 17° with 50 per cent humidity is very favorable for good hatches, 

 but development is very* slow. 



Lc^rvo'e. — A temperature of 37° kills the larvae in a few hours; 32° is very 

 unfavorable, especially with high humidity; 27° is favorable with high hu- 

 midity and unfavorable with low hmnidity^; 22° is very favorable with all hu- 

 midities used; 17° with 50 per cent humidity is very favorable for a high per- 

 centage maturing, but development is exceedingly slow. 



Climatic conditions in the Upper Austral Zone of Massachusetts, Connecti- 

 cut and Rhode Island are favorable for the development of the Mexican beare 

 beetle, and the insect may therefore be expected to become a serious pest. 

 Conditions in the Transition Zone are less favorable, but the insect will prob- 

 ably become a pest in the lower portion of the Zone, with the injury becom- 

 ing greatly reduced as the upper limits are approached. The Canadian Zone! 

 of New England does not have a physical environment suitable for the de- 

 velopment of the beetle. 



Literature Cited 



Cecil, R. 



1928. The Mexican bean beetle. 



N. Y. (Geneva) Agr. Exp. Sta. Cir. 96:1-12. 

 De Long, D. M. 



1926. (Discussion) Jour. Econ. Ent. 19:247-248. 



Douglass, J. R. 



1928. Precipitation as a factor in the emergence of Epilachna oorrupta 

 from hibernation. Jour. Econ. Ent. 21:203-213. 



Eddy, C. O. 



1926. The Mexican bean beetle in South Carolina. 

 Jour. Econ. Ent. 19:239-247. 



Eddy, C. O. and McAllister, L. C, Jr. 



1927. The Mexican bean beetle. S. C. Agr. Exp. Sta. Bui. 236:1-38. 

 Eddy, C. O. and Clarke, W. H. 



1929. The Mexican bean beetle in 1927-8. 

 S. C. Agr. Exp. Sta. Bui. 258:1-41. 



Fernald, H. T. 



1915. Some present needs in economic entomology. 



Jour. Econ. Ent. 8:36-38. 



