588 Pz\MILV XXIV. DERMKSTID.H. 



partly covered with pale ai'i.v or brown spots composed of minute 

 scales or hairs which are easily nibbed otiP. When clisturbecl they 

 usually ''play possum," folding back their legs and rolling over on 

 their backs, where the}- remain quiescent for some time. The name 

 of the typical genus, I)< i-iiustcf:, is derived from two Greek words 

 meaning "a skin" and "to devour," whence the common name of 

 skin-eaters or skin beetles. 



The principal distinguishing characters of the family are the 

 small deflexed head; eyes rounded, with small facets, the front 

 usually with a third simple eye or ocellus ; antenna- short, inserted 

 in front of eyes, usually 11-, sometimes 0- or 10-jointed, the last 

 two or three joints forming a large club; thorax short, in the ma- 

 jority of species excavated beneath for the reception of the an- 

 tennte; elytra covering the abdomen, not striate; abdomen with five 

 free ventral segments: front coxa- i-ather long, conical or oblique, 

 the cavities open behind except in Bi/luriis: middle coxie oval, 

 oblique; hind coxu' slightly separated, usually dilated into a plate 

 partly protecting the femora and formed to receive the latter in 

 repose; legs short, tibia^ with distinct spurs; tarsi 5-jointed, claws 

 usually simple. 



The larva' of the majority of Dermestids are brown, active grubs 

 clothed with long hairs and usually with a brush of similar hairs at 

 the end of the body. Many of them have a peculiar gait, running 

 for a short distance, then stopping and vi1n-ating the hairs with 

 great rapidity. They are much more destructive than the adult 

 beetles, but at times appear to be able to live for loug periods with 

 little or no food. 



Between 800 and 400 species of Dermestida^ are known, about 8.") 

 of which, with numerous varieties, are from North America. The 

 principal literature treating of these is as follows; 



Lef'ontc. — "Syiioij.'-is of the Dermestida'' of the United States." 

 iv Proe. Phil. Acad. Nat. Sci., VIII, 1854. 106-11.8. 



■Janiif. — "Revision of the Dermestida' of the United States," iji 

 Proc. Amer. Phil. Soc. XX, 1882. :U3-:!77. 



Casnj. — "Review of the American l>ermeslida>," in Journ, N. 



y. Eiit. Soc. vin, i!)(io, i:;8-i(i,-,. 



The memliers of the family whi<'h have a range including Indi- 

 ana are distriliuted ainen'.v eight genera. 



KEY TO INDI.VN.V nFNi:H.\ OF IIKIUtKSTID.1^. 



a. Tarsi with seconrl and third .ioints lobed beneath ; Ivnnt cn.xal cavitie-; 

 closed behind; claws armed with u lar,:;i' liasnl tooth. < Fi.n. l'21.) 



I. BYTUKVsi. 



