188 INSECT PESTS OF FARM, GARDEN AND ORCHARD 



cycle requires from six to ten weeks, but in summer it is reduced 

 to about twenty-five days. Thus there are from three to six 

 or more generations during a season, according to the latitude. 

 The Red or Square-necked Grain-beetle * is about the same 

 size as the last species, but is of a reddish-brown color, and the 

 thorax is almost square, nearly as broad as the abdomen, and 

 not notched on the sides. It breeds in corn in the field and in 

 the granary, first destroying the germ, so that it is especially 



a, 



FIG. 137. The saw-toothed grain beetle (Silvanus surinamensis): a, adult 

 beetle; b, pupa; c, larva all enlarged; d, antenna of larva still more 

 enlarged; d, the red or square-necked grain beetle (Cathartus gemellatus 

 Duv.) (After Chittenden, U. S. Dept. Agr.) 



injurious to seed-corn. It feeds mostly out of doors, though 

 sometimes infesting the granary. 



The Foreign Grain-beetle f is of much the same general 

 appearance, but smaller and of a more robust appearance It 

 feeds upon a great variety of stored products as well as grain, 

 but rarely becomes troublesome. 



The Cadelle J also has the bad habit of first attacking the 

 embryo or germ of the kernel, and going from one kernel to another, 

 thus destroys a large number for seed purposes. It possesses, 



* Cathartus gemellatus Duv. 



t Cathartus advena Waltl. 



t Tenebroides manritanicus Linn. Family Trogositidce. 



