AMERICAN COLEOPTERA. 321 



obtusely rounded, twice as long as thorax, above almost flat, 

 distinctly striate, striae sub-remotely punctured ; intervals flat, very 

 finely transversely strigose; color ferruginous slightly shining, with 

 numerous short whitish lines in the intervals and at the sides sinuately 

 and at apex transversely black. Pygidium serui-orbiculate, either en- 

 tirely cinereo-tomentose or with a median line of same color. Body 

 beneath obsoletely punctulate, black, finely cinereo-tomentose. Mid- 

 dle and anterior legs more slender, rufo-testaceous ; posterior legs ro- 

 bust, femora thick, often black, cinereo-tomentose, beneath near apex 

 armed with a moderate tooth, tibiae and tarsi testaceous. 



Varies with the elytra entirely black. 



The above description, which is a translation of that of Schonherr, 

 indicates a species totally differing from any known to me. It cannot 

 be definitely stated that it is a member of the present group, although 

 associated, by Schonherr, with other species with the armature of hind 

 femur peculiar here; in fact in but one instance has Schonherr stated 

 the existance of an external as well as internal tooth. The matter is 

 left for the discoveries of future collectors who will be rewarded with 

 one of the largest species in our fauna. 



Group IV. 



This group contains those species in which the femur becomes quite 

 slender and has neither tooth nor denticle. All the species in our 

 fauna are short, sub-quadrate, and of robust form. Thorax short, 

 always twice as broad at base as long. In the males the antennae are 

 pectinate or even flabellate, the eyes large and nearly contiguous on 

 the middle line of the front. 



Three species are known. 



Elytra black, with large red space on each discoideiiM. 



Elytra rufous, with coarse perforations corypha*. 



Elytra dark rufous, humeri and apex with small black spot, surface variegated 



with whitish pubescence impiger. 



B. discoideus, Say, Journ. Acad., Ser. 1, vol. iii., p. 307.— Short, robust, 

 black, sub opaque, elytra with large red spot on each near the side. Pygidium 

 nearly vertical, desely clothed with whitish pubescence and with four small 

 black spots. Body beneath black, clothed with whitish pubescence. Head 

 black, sub-opaque, densely punctured, front carinate. Antennse black, slightly 

 longer than head and thorax, serrate £> or flabellate % from the fourth joint, 

 the branches very long. Thorax trapezoidal, nearly twice as wide at base as 

 long, anteriorly truncate, base trisinuate, median lobe prominent, emarginate 

 at tip; sides slightly arcuate ; median line finely impressed, on each side of 

 which near the base a broad tubercle, surface coarsely punctured, sub-opaque 

 sparsely clothed with whitish hairs. Seutellum black, cinereo-pubescent, con- 



