392 AJfTHRIBID^. LLeConte. 



The prosternal sutures are entirely obliterated, as is also the short suture 

 behind the posterior point of the prosternum.so that the under surftxce con- 

 sists of but one piece. The coxal cavities are rounded, and narrowly sep- 

 arated. 



Mesosternum flat, triangular behind, with the point rounded, and sepa- 

 rating the middle coxae; cavities rounded, epiraera transverse, oblique, not 

 attaining the coxae. 



Metasternum long, side pieces narrow, or moderate in width, wider in 

 front, with the outer angle prolonged forwards; in many genera there is a 

 transverse impression in front, simulating a suture. 



Elytra conjointly rounded behind, and forming a small sutural fold, 

 which fits into a deep emargination of the pj^gidium ; fold of the inner sur- 

 face acute, not prolonged much behind the middle. Epipleun^ distinct. 

 The stripe are ten in number, with a short scutellar one as in Carabidw; 

 this scutellar stria is usually about one-fourth the length of the elytra, and 

 does not connect itself with the sutural stria. 



Abdomen with five free, and sometimes nearly equal ventral segments; 

 sutures straight; intercoxal process triangular, acute or rounded in front; 

 dorsal segment membranous, except the pygidium, which is corneous, de- 

 clivous and exposed ; no anal segment in the (^. 



Anterior coxae narrowly separated, globose; middle coxae moderately sep- 

 arated, rounded; hind coxae transverse, not prominent, never very widely 

 separated. 



Legs slender, front pair sometimes elongated in (J'; tibiae truncate at tip, 

 without spurs or hooks. 



Tarsi brush like beneath, 4-jointed; second joint triangular, emarginate.; 

 third joint bilobed, sometimes large, sometimes small; fourth joint slender 

 with divergent claws, which are either simple or toothed. 



Our genera represent four tribes: 

 Antennae inserted at the sides of the beak; 



Prothoracic ridge not basal TROPIDERINI. 



Prothoracic ridge basal BASlTROl>l!«I. 



Antennae inserted on the front; prothoracic ridge 

 basal ; 



Elytra striate as usual AR^OCERINI. 



Elytra not striate xemorchestini. 



Tribe I. tropiderini. 



The genera of this tribe are sufficiently distinguished by the position and 

 form of the prothoracic ridge, which is remote from the base, more or less 

 sinuous, and flexed obliquely at the sides. The antennae are situated under 

 the lateral edge of the beak, which is sometimes flattened and expanded so 

 that the antennal cavi:ies are partially covered. 

 Three groups occur in our founa: 



Eyes entire, suture of mentum obliterated 2. 



" emarginate; suture of mentum distinct Hormiscl. 



