64 



THE ORDER OF COLEOPTERA. 



posed of a little lamella or plate, supported at the eud of a slender foot- 

 stalk, aud ornamented with a fringe of long hairs. In some the wings 

 are wanting. The elytra are sometimes truncated. The club of the 

 antenna? is usually four, rarely two jointed. The tarsi are only three 

 jointed, with a club-tipt bristle between the claws. The surface is often 

 pubescent. Some live in rotten wood and others in manure; a few have 

 been found in ants' nests. 

 Thirty-eight jST. American species have been described. 



Family XVIII. SCYDM^NID^. 



This is another family of very small insects, found under stones or in 

 waste matter, and in ants' nests. They are of a brown color, and are 

 clothed with erect hairs. They are frequently seen flying in twilight. 

 They are very easjily distinguished from the small beetles of the three 

 preceding families, by their more oblong ovate form, by the head sepa 

 rated from the pro-thorax by a distinct neck, and by their large abdo- 

 mens, much wider than the somewhat egg-shaped thorax. They bear 

 the closest relationship to the more extensive family of Pselaphidee, 

 treated of below, from which, however, they are strongly separated by 

 their five jointed tarsi, and their elytra covering the whole abdomen. 



Thirty-eight N. A. species already described. 



[Fig. 26.] 



Family XIX. TROGOSITID.E. 



Founded upon the genus Trogosita, of Olivier, a name composed of the 

 Greek words trogo — to eat, and fiitos — grain, and originally applied to the 

 most notorious species, the Trogosita mauritanica, (Tcnehrio niauritani- 



cus, Linn.) because it is often 

 found in great numbers in 

 worm-infested granaries. But 

 observations recently made up- 

 on the carnivorous habits of 

 other species of the genus, ren- 

 der it probable that the larva? 

 of the T. mauritaiiica live upon 

 the larv;e of the Calandrai and 

 TuoGosiTA couTicAus, Moish.:— a, larva: c, its niamii- Tiniii', which are the real au- 



blfi; rf. antenTia: e. iiiuler siilc of head : /, the two-h(iruc(l 



anal plate; 6, the beetle ; h, its antenna'; i, mandible; g, tllOrS of tllC damage. Tllis XIBW 



labium and its palpi ; j, one of the maxilhe and its palpus 



—alter Kiiey. is confirmed by our own obser- 



tions upon the larva of a common American species, the Trogosita 

 corticaUs, of JNIelsheimer, which we have seen preying upon the larva of 

 the Codling-moth ( Carpocapsa pomoneUa). The Trogositidiie are oblong, 

 somewhat depressed or flattened beetles, of a black or reddish black 



