224 CURCULIONID^. 



[LeConte. 



in common with several otlier tribes, the bealc is received upon the 

 sternum, and lies in repose in a pectoral groove, this tribe differs from 

 Zygopini in the smaller size, and different position of the eyes, which are 

 more or less covered by the prothoracic lobes; and from CeutorhyncMni by 

 the pygidium being entirely covered. 



The pectoral groove varies in length according to the group; the front 

 coxae are contiguous in many species of ConotracJielus, and other genera 

 of the group Ithypori. The side pieces of the mesothorax are obliquely di- 

 vided, and the epimera attain largely the base of the prothorax on the 

 under surface, without intervening between the pronotum and the elytra. 

 The metasternum is either long or short; the side pieces narrow, and di. 

 lated in front. The ventral segments vary in length; the first suture is 

 straight or sinuate, deep, or obliterated; the second and third are some- 

 what angulated at the sides. The tibiije are armed with a strong hook at 

 the tip, and the articular surface is oblique; the claws are simple, or 

 toothed. 



But three groups are represented in our fauna, of which the second is es- 

 tablished upon a new genus. 



Pectoral groove confined to the prosternum, open behind : 



Beak long, tarsi dilated Ithypori. 



Beak short, tarsi narrow Acampti. 



Pectoral groove extending to the mesosternum, sharply 



limited behind Cryptorbyncbl. 



Group I. Itbypori. 



In this group the pectoral groove is confined to the prosternum, and is 

 not closed behind, .the mesosternum is sometimes flat, sometimes suddenly 

 declivous. The eyes are coarsely granulated, partly covered in repose by 

 the prothoracic lobes, which are sometimes very well developed, but in other 

 genera are broad and not prominent. 



The prothorax is, in most species, comparatively smaller than in the other 

 groups, and usually very coarsely sculptured. The elytra are wider than 

 the prothorax, with prominent humeri, the outer stria is usually abbre- 

 viated, and there is a tendency to an epipleural fold. The thighs are 

 toothed in our genera; the tibife slender, hooked at the tip; the claws 

 usually toothed, though sometimes simple, or even connate at the base. 



The front coxae are sometimes contiguous, a character not observed in the 

 other groups of this tribe. 



Postocular lobes broad, not prominent 2. 



" " prominent, front coxae contig- 

 uous; claws toothed; sometimes cleft CONOTRACHELiUS. 



2. Claws slender, simple 3. 



" approximate, toothed RHYSSEMATTJS. 



connate at base OHALOODERMUS. 



3. Elytra at base not wider than prothorax ZAGLYPTUS. 



" " " much wider MICROHYUS. 



