178 



COLEOPTERA— BEETLES 



tlie fact tliat they become very numerous in mills it is quite 

 probable that eggs may be included in the i)ackage and the 

 larva^ de\el(>ped later. 



Family Lyctidae. — The family Lydidce includes a number 

 of wood-feeding species, for which the powder-post beetle 

 {Lydvs planicoUis) will serve as a fair example. 



Dermestidae.— The Dermestidoe are forms that live on 

 decaying animal matter. Good examples may be found by 



Fig. 127. — The saw-toothed grain beetle: a, adult; b, pupa; c, larva 

 or grub. Greatly enlarged. (After Chittenden, Div. Ent., Bull. 4, n. s., 

 1896. U. S. Dept. Ag.) 



examining dead fish and other decaying organic matter. 

 Some of the species are museum pests, and troublesome in 

 bird collections, and a very particular pest of insect collec- 

 tions. On account of this it is necessary to keep collections 

 in insect-proof boxes or else fumigate with carbon bisulphide. 

 Larder Beetles (Dermestes lardarius). — The adults appear 

 particularly in early summer and the eggs are deposited on 

 or near materials that furnish food for the larva^. The eggs 



