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SCHOOL ENTOMOLOGY 



The beetles are quite long-lived, and thus do considerable 

 damage. As there are three or four broods in the North and 

 six or more in the South, it has been estimated that the 

 progeny of one pair would amount to 6000 insects in a single 

 season. 



Another beetle very common in the granary, but of quite 

 different appearance, is the Saw-toothed Grain-beetle * (Fig. 

 159). It is a cosmopolitan pest and is nearly omnivor 



FIG. 159. The saw-toothed grain-beetle (Silvanus surinamensis) . 

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



a, adult beetle; 6, pupa; c, larva all enlarged; d, the red or square-necked 

 grain-beetle (Cathartus gemellatus) . 



ous. The beetle is only about one-tenth of an inch long, 

 very much flattened, of a dark-brown cojor, and may be 

 easily recognized by the six saw-like teeth on each side of the 

 thorax. The larva is of a dirty-white color, and quite dis- 

 similar from that of the granary weevil. Having six legs to 

 carry it about, it is not satisfied with a single seed, but runs 

 about here and there, nibbling at several. When full grown 

 the larva glues together several grains or fragments into a 

 * Silvanus surinamensis Linn. Family Cucujidaz. 



