306 CURCULIONIDJE. 



[LeConte. 



One specimen, collected by me near the Rocky Mountains. The scales 

 are partly abraded; on the elytra they remain only at the base and near the 

 extremity of the fourth to the seventh interspaces. 



CEISTTRINUS Sch. 



After separating a certain number of species, which seem to indicate 

 distinct and well-defined genera, there remains a tolerably numerous mass, 

 which, although not entirely homogeneous, consists of species having in 

 common the following characters. The study of foreign species may per- 

 mit at a future time a farther subdivision, but the transition between the 

 extreme forms seems so gradual, that I am unwilling, wfth my present 

 knowledge, to indicate the manner in which this may be effected. 



The beak is long and slender, cylindrical, and usually curved, but some- 

 times nearly straight; the antennal grooves commence about the middle, 

 descend obliquely, and are wider, deeper and confluent behind. Mandi- 

 bles small, flattened, pointed, prominent, and without teeth. Antennce 

 rather slender, funicle 7-jointed, joints 1-3 varying in length, 4-7 equal 

 in length, not passing into the club, which is oval, somewhat pointed, pu- 

 bescent and annulated. Prothorax narrowed and more or less constricted 

 in front, without postocular lobes; prosternum long in front of the coxa?, 

 which are rather widely separated ; not emarginate in front, impressed or 

 not, according to species. Elytra sometimes elongate with parallel sides, 

 though usually narrowed from the humeri, so as to give a rhomboidal form 

 of body; posterior callosity feeble, tips usually conjointly rounded, some- 

 times separately rounded, exposing in the latter case a small part of the 

 pygidium, which is, however, horizontal, and not vertical, as in Baris and 

 its allies. The middle and hind coxoe are widely separated; metasternum 

 rather short, with wide episterna in the rhomboidal species; longer, with 

 narrower episterna in the elongate species; but in both cases distinctly 

 wider before and behind. Ventral surface ascending in some species, 

 nearly horizontal in others; first and second joints longer than third and 

 fourth ; fifth sometimes longer, sometimes not longer than the fourth : 

 first suture subsinuate, the others strongly angulated at the sides. 

 Thighs unarmed, tibise not striate on the outer side, very feebly mucronate 

 at tip; tarsi with the third joint very broad, bilobed, last joint long, with 

 stout, divergent claws. 



In the males of several species the prosternum just in front of the coxae is 

 armed with a slender process, which varies in length according to the in- 

 dividual, but not according to species. 



A. Elytra separately strongly rounded at tip; pygidium partly exposed; 

 posterior edge of prothorax deeply emarginate beneath in front of 

 mesosternum. 



Black, densely punctured ; above pruinose, 

 with fine scales or hairs, beneath scaly; 

 scutellum clothed with white scales 1. scutellum- album. 



