NORTH AMERICAN COLEOPTERA. 171 



lar, the first longer, third broader and bilobed, the fourth on the 

 posterior legs globosely inflated at apex. The claws appendiculate. 

 Form oblong, surfiiee glabrous, body winged. 



This genus is now for the first time fully described, although 

 Melsheimer described the species on which it is based in 1847. The 

 question of the validity of Pachyonychus and Pachyonychis has 

 been amply discussed by Crotch (Proc. Acad. 1873, p. 58), and by 

 Jacoby and myself (Trans. Am. Ent. Soc. xv, pp. 302-304), and 

 will not be dwelt upon at this time. At that time the suggestion was 

 made that it might be related to Cerichrestus, which now seems to 

 me not well founded. At present I am unable to suggest any special 

 relationship for it, although by the table given by Chapuis it must 

 be placed near Omototus and Hypolampsis. 



One species is known to me. 



P. paradoxus Mels. — Oblong, nearly parallel, nifotestaceous, shining, 

 elytra pioeoiis, the niarsin narrowly, the suture broadly rufotestaceous. Antennae 

 black, the three basal joints rufotestaceous. Head smooth, shining. Thorax 

 more than one-half broader than long, not narrowed in front, sides feebly arcu- 

 ate, margin thickened at front angles, posterior angles rather acutt, disc convex, 

 irregularly sparsely punctate, the ante-basal impression deep, extending from 

 side to side within the angles. Elytra wider at base than the thorax, humeri 

 obtusely prominent, umbone distinct, base cmarginate at middle, sides feebly 

 arcuate, apical angles well defined, disc moderately convex, regularly punctato- 

 striate, stride not deeply impressed, punctures moderately coarse and closely 

 placed, intervals slightly convex, broader than the strise, each with a row of 

 very fine punctures. Abdomen sparsely punctate and slightly pubescent. 

 Length .12— .18 inch. ; 3—4.5 mm. PI. vii, fig. 1. 



No sexual characters have been observed in the seven specimens 

 before me. 



Occurs in the Middle States region ; sometimes abundant in Dis- 

 trict of Columbia (TJlke). 



HYPOI.AMPSIS Clark. 



Head moderately deeply inserted, the eyes free, clypeus somewhat 

 prolonged, truncate, front very obtusely carinate, the tubercles dis- 

 tinct. Eyes oval, convex, coarsely granulated. Labrum transverse, 

 slightly emarginate. Antenme rather stout, not longer than half the 

 body, the five outer joints rather abruptly broader, forming an elon- 

 gate club which is opaque, and with dense fine pubescence, first five 

 joints not densely pubescent, shining; first joint clavate, second ob- 

 long oval, as stout as first, but shorter, third more slender, longer 



