30 COLEOPTERA. 



The smaller genera of the family, such as Choleva, Latr., and 

 Colon, Herbst, include very active insects, not averaging more than 

 one-sixth of an inch in length, and generally of dull colours; they 

 feed on decaying animal and vegetable matter. 



Family IV. — Trichoptenjgidce. 



Tarsi three-jointed ; antennas eleven-jointed, clothed with long 

 hairs, the three last joints thickened. 



These small dark-coloured beetles are the smallest of all the 

 Coleoptera, and many do not exceed one-twentieth or one-thirtieth 

 of an inch in length. They are found in decaying vegetable 

 matter, under bark, in ants' nests, etc. 



Family V. — Eisteridce. 



Tarsi five-jointed; mandibles prominent; antennre short, ending 

 in a large three-jointed club; body square or oblong-quadrate, 

 flattened or convex, very hard and polished ; elytra truncated ; 

 legs contractile ; front legs dentated or spined on the outside. 



The Histeridce are small black beetles, which play the part of 

 general scavengers, feeding on dung, carrion, and decaying animal 

 and vegetable matter generally. Several species are adorned with 

 bright red spots or markings, and a few are metallic. They may 

 often be seen running on paths in the day-time, like other beetles 

 of similar habits, but some of the smaller species are met with 

 under bark, and in ants' nests. 



In general the Histeridce are short and broad, and a few figures 

 will give a sufiiciently good idea of the appearance of the whole. 

 Most of the species are black and shining. In Hololepta Fossularis, 

 Say, the mandibles are unusually prominent ; it is found under bark 

 in the United States. Platysoma Coardahmi, Lee, is another North 

 American species of a more elongated form than is usual in this 

 family. The typical genus Histcr, Linn., is of considerable extent, 

 and is fairly well represented in all parts of the world. Hister 

 Bimaculatus, Linn., a common European species about one-fifth of 

 an inch in length, is black and shining, with reddish legs and 

 antennae, and six raised stripes on each elytron. At th*^- outer 

 angle at the tip of each is a rather large reddish-yellow spot. 



Family VI. — NitidtiUdce. 



Tarsi five-jointed, the first three generally enlarged, the fourth 

 minute ; body compact, oval : elytra sometimes covering the whole 



