TRICIIOPTERYGID^. 443 



with striae ; some few species of Hister and Saprinus have the 

 elytra marked with red, and a few of the latter genus are 

 metallic in color. The form of the body is variable ; those of 

 the first group are oblong and flat, with prominent mandibles ; 

 the others are round, oblong oval, globose, some depressed 

 and some convex. The species live under the bark of trees, in 

 excrement and in carcasses. When disturbed the insects 

 retract the antennae and feet, appearing as if dead. The an- 

 tennae are geniculate, the eighth and following joints forming 

 a compact annulated, rounded or (rarely) triangular club. 

 The elytra are truncate behind, leaving two segments of the 

 abdomen uncovered. The linear flattened larvae have the ter- 

 minal ring ending in two biarticulated appendages, and a 

 single anal prop-leg. The larva of the European Hister 

 vierdarius (Fig. 390) lives in cow dung, forming a cell in 

 which it transforms, and like Authrenus, the pale brown 

 pupa retains the larva skin about it. In Hister the head 

 is retracted and bent downwards, and the club of the 

 antenna is round and annulated. Hister interruptus 

 Beauv. and A. marginicollis Lee. are common northward. Fig. 390 

 The genus Hetarrins differs in the antennal club being 

 obconical, truncate and solid. The species are found only in 

 ants' nests early in the spring. In Saprinus the antennae are 

 inserted under the margin of the front ; the antennal cavities 

 being at the sides of the prosternum proper. The species are 

 mostly found in carrion and in dung. 



ScAPHiDiiD.E MacLeay. "This family," according to Dr. 

 Leconte, "contains small oval or rounded oval, convex, very 

 shining insects, living in fungi. The sides of the thorax are 

 oblique, and the head small, so as to make the body somewhat 

 pointed in front ; the thorax is very closely applied to the 

 front, and the elytra are broadly truncate, permitting the tip 

 of the conical abdomen to appear." In SccqMcliiim the an- 

 tennae are clavate, the ej'es emarginate, the posterior tibiae are 

 not spinous, and the flrst joint of the posterior tarsi longest. 



TRicnoPTEnTCriD.F. (Trichopterygia Erichson). This incon- 

 siderable family comprises the smallest beetles known. The 



