BEHAVIOR OF SPIDERS AND OTHER INSECTS 405 



MIGRATION 



Harte (54) describes the flight of the cotton moth in 1911, 

 and Unsicker (108) the migration of the buck moth (Hemiluca 

 ma ia ) . 



According to Cockerell (27), at Boulder, Colorado, July 1st, 

 a bug (Lygaeus facctus Say) appeared in incalculable numbers. 

 In some parts of the town they were so thick that they were 

 swept up with brooms. He thinks the migration was due to 

 the drying up of their food plants. 



Ewing (38) relates that in Oregon the lady-bug beetle (Hip- 

 podamia convergens Guerin) spends the spring and the summer 

 in the lower altitudes and the fall and the winter in the higher. 

 Although there is no fixed migration, when the aphids are few 

 large numbers of these beetles move in certain directions in 

 search of pollen. By the middle of August all have quit the 

 hot, dry, valleys and moved upwards. 



LOCOMOTION 



Claude (25) discusses jumping spiders, Hodge (59) how far 

 flies may travel over water, and Girault (50) the swimming of 

 certain Tettigids. 



Girault (49) amputated the antennae of several different spe- 

 cies of moths by snipping them about an eight of an inch from 

 the head. The flight of such individuals was irregular and tended 

 to become circular. 



Fabre (39) performed some experiments demonstrating the 

 details of the manner in which young spiders take their " bal- 

 loon flights." 



See Zetek (126) under technique. 



ECOLOGY 



Bailey (4) discusses the faunal zones of Mexico and Walker 

 (112) those of Canada. 



Vestal (110) has made an intensive ecological study of the 

 species of grasshoppers of a limited area. 



Brues (18) has been studying the distribution of the stable 

 fly, which is the carrier of anthrax, infantile paralysis, etc. 

 Next to the house fly, this is the most widely distributed of all 

 insects. It occurs in every zoological region and practically 

 throughout most of them. It is more abundant in temperate 

 than in tropical regions. 



