554 TRANSACTIONS OP THE 



excepting a marginal interrupted one ; an indentation each side 

 of the scutel and on the humerus. 

 Length four-fifths of an inch. 



The dilated basal thoracic lines deeply indenting the posterior 

 edge, together with the three intervening punctures will readily 

 distinguish [440] this species. At first view it resembles B. 

 flavicaude Say, but is more highly j^olished. 



[Belongs to Tacliys. — Lec] 



15. B. INCURVUM. — Piceous ; elytra with a honey-yellow vitta 

 from the humerus, a little dilated at its termination before the 

 tip. 



Inhabits Indiana. 



Body piceous ; head blackish-piceous ; antennse honey -yellow ; 

 thorax a little contracted gradually to the base ; dorsal line slen- 

 der and slightly impressed ; basal transverse line deeply impressed, 

 with numerous minute wrinkles ; basal lines dilated, undulating 

 the posterior edge ; elytra polished, with a profoundly impressed, 

 somewhat dilated, simple, sutural stride ; the second stria obso- 

 lete ; an interrupted stria on the lateral margin ; a dilated inden- 

 tation each side of the scutel, and a smaller one on the humerus; 

 a dilated vitta from the humerus, near its tip, curves a little to- 

 wards the suture; and is in that part a little more dilated ; venter 

 black piceous ; feet honey-yellow. 



Length over four-fiftieths of an inch. 



Resembles the preceding, but is destitute of the three punctures 

 at the base of the thorax, and with that species belongs probably 

 to Peryplms Meg. 



Of the genus Bemhidium Latr. I have twenty-two described 

 species natives of North America. 



[Also a Tachys. — Lec] 



DYTISCUS Linn. Latr. 

 1. D. CONFLUENS. — Blackish-brown margined with honey-yel- 

 low ; four exterior grooves of the elytra nearly or quite gemi- 

 nately confluent at tip. 

 Inhabits Maine. 



Body blackish-brown with a green reflection, covered above 

 Avith minute punctures ; head dark green, with a frontal rufous 



[Vol. IV. 



