October, 1844.] 109 



2. R. erythropterus. Black ; antennae, elytra and feet rufous. — \ 1. long. 

 Pennsylvania. Bank of the Susquehanna. 



Elongate : head dull rufo-piceous, somewhat depressed above, much punc- 

 tulate, with short obsolete longitudinal striae on the vertex ; clypeus slightly 

 longitudinally convex : antennae rufous, the clava short, ovate, with the 

 joints compact : thorax as wide as the elytra, subquadrate, truncate at apex 

 and base, the sides and posterior angles obtusely rounded ; disk somewhat 

 depressed, with deep and distant punctures ; lateral margins more numerously 

 punctulate ; each side of the middle with an impressed longitudinal line, 

 bounded at base by an obsolete transverse one : scutel triangular, rounded at 

 tip: elytra rufous, dusky, truncate and slightly narrowed at apex ; obsoletely 

 punctate-striate, the striae fine, distinct : epipleuras and feet rufous : pygidium 

 exposed, strongly punctulate : beneath black. 



Trogosita, Fabr. 



1. T. castanea. Black above, beneath and feet reddish-brown; head an- 

 teriorly obsoletely rufous. 5^ 1. long, 2\ 1. wide. Pennsylvania. 



Trogosita castanea, Melsh Catal. 



Closely allied if not the same, to cinnamonea, Say, but it differs from that 

 species in being differently colored, in having the head and thorax more dis- 

 tinctly punctured, in^the elytra being always comparatively wider and deci- 

 dedly differently engraved ; in the present species the striae and punctures 

 are obsolete and the surface much wrinkled. Say, in a letter, considers cas- 

 tanea identical with his cinnamonea. 



2. T. corticalis. Black; antennae and feet piceous ; elytra profoundly 

 punctate striate. 4J 1. long, 1^1. wide. Pennsylvania. 



Trogosita corticalis, Melsh. Catal. 



subnigra, Beauv. Ins. p. 127, pi. 32, f. 9.? 



Body subelliptic, black : head with large, deep and vicinal punctures ; a 

 punctiform impression between the eyes : mandibles black : antennae piceous : 

 thorax subquadrate, obviously widest at base, with the sides feebly arcuated ; 

 surface punctured like the head, with a narrow impunctured dorsal space ; 

 posterior angles minute, acute, excurved : elytra with the sides almost paral- 

 lel from the humeral angle to near the tip ; deeply punctate-striate, the in- 

 terstices each form two series of minute oblong distant punctures: beneath 

 and feet piceous. This species can hardly be either T. depressior or subni- 

 gra of Pal. de Beauv., if his figures and descriptions of these two species be 

 correct. 



3. T. limbalis. Dull rufo-piceous, with the disk of the thorax and elytra 

 blackish. 4 1. long, 1| wide. Pennsylvania. 



Form entirely that of the preceding ; head black, tinged with dull rufous 

 at the sides ; sculptured as in the preceding : antenna rufo-piceous : thorax 

 black, with the lateral margins broadly dull rufo-piceous ; contour and en- 

 graving as in the preceding, with the impunctured dorsal space more feebly 

 defined : elytra dull rufous, with the sutural region dusky or blackisk ; sides 

 somewhat less parallel than in the preceding species ; finely punctate-striate, 

 the interstices flat and transversely finely wrinkled : venter and postpectus 



