112 EXTRACTS. 



Grasshoppers and Birds. — Of fifteen species of birds 

 occurring in the Nicola Valley, British Columbia, the food 

 was found to consist largely of grasshoppers, and in some 

 cases grasshoppers formed 42 per cent, of the total. {Taylor, 

 L. E., Proc. Ent. Soc. Brit. Colmh. Victoria, ^Yo, 7, 1915.) 



Codling Moths and Temperature. — There is a type of injury 

 in New York State due to larvpe hatching from eggs 

 deposited in June or early July, after the fruit has attained 

 a considerable size. This is said to be prevalent in localities 

 where a large body of water prevented a marked rise of 

 evening temperature in the spring. Eggs are rarely 

 deposited when the evening temperature falls below 60^ F. 

 Records from inland districts, removed from the influence of 

 water, have shown that at temperatures above 60° F. egg- 

 laying proceeds normally. {Felt, E. P., Jl. Econ. Ent. 

 Concord, ix. 1, 1916). 



Rontgen Rags and Insect Control. — Under laboratory con- 

 ditions tests made with a Kontgen-ray tube permitting a 

 high-energy input and giving an intense and powerful 

 radiation gave results wliich promise that the X-ray process 

 may be successfully used in the treatment of cigars or 

 tobacco infested with the cigarette beetle (Lasioderma 

 serricorne). In treating the egg-stage heavier exposures 

 are re(|uired to sterilise eggs which are near the hatching- 

 point than newly laid ones. A dosage equivalent to 150 

 milliampcre minutes exposure with a spark-gap of 5'5 inches 

 gave satisfactory results with eggs in tobacco placed 7*5 

 inches from the focal spot of the tube. Witli this exposure 

 the eggs in which embryonic development was well advanced 

 hatched, but in all cases where th.ese larvae were kept under 

 observation they failed to reach the adult stage. In two 

 se[)arate experiments adults were given an exposure of 600 

 milliampei'e minutes, with a s[)ark-gap of 5*5 inches, giving 

 an approximate voltage of 65,000, with humidity at 57. The 

 distance from the focal spot of the R()ntgen tube was 7*5 

 inches. No effect on the length of life was apparent, as the 

 beetles died at about the same rate as the same number of 



