339 

 Js^OTONECTID^E. 



In'otonecta, Linn. 



N. insulata. 



Notonecta insulata, Kirby, Fauna Bor.-Amer. iv, 285, No. 399 

 Notonecta rmjosa, Fieb., Rhyuchotograpbien, 52, No. 7. 



Mountains of Colorado, July (Lieutenant Carpenter). 



The immediate vicinity of Baltimore no longer admits this species, 

 although it at one time inhabited the pools of spring-water, as well as 

 the little basins themselves which the springs excavated in their out- 

 ward flow. Now, the waters are polluted by the foulness of the drainage, 

 while many of them have become obliterated by drying, up. Still, at a 

 distance of twenty miles or more from the city, here and there a basin of 

 clear cold spring-water still remains, and in this a few specimens may be 

 occasionally met with. 



Our common species, the X. undulate, Say, on the contrary, inhabits 

 the foulest pools. And in the dirty slush occasioned by the drainage of 

 slaughter-houses, and in the slimy ponds attached to some of our brick- 

 yards, it revels as if in full enjoyment of the filth. 



COEISID^tE. 



CoKixA, Geoff. 

 1. C. sutilis. jSTew sp. 



Long and moderately narrow; dark brown, opaque, marked with tes- 

 taceous. Head angular ; face moderately broad, pale testaceous, with a 

 range of golden bristles along the margins, inferiorly, of the fovea of the 

 male, and at the apex of the epistoma is a dense tuft of similar, but 

 longer, bristles. Outer margins of the fovea carinated, and the adjoining 

 surface coarsely jpunctate; the fore part of cranium embrowned, and with 

 three or four series of coarse shallow punctures each side; middle line ele- 

 vated, tapering posteriorly, and terminating in an acute point on the 

 angular tip of the occiput ; posterior edges of the headcarinately elevated. 

 Pronotum short, broad-cordate, emarginate in front, rastrated, with twelve 

 to fourteen closely-placed yellow lines, of which two or three on the middle 

 are forked at the ends ; medial line acutely, almost percurrently, cari- 

 nate ; lateral margins brown. Pleura dull black, the upper part of the 

 pieces more or less broadly testaceous. Legs pale testaceous ; palte 

 falcate, a little curved at tip, moderately narrow, tapering, acute, scarcely 

 differing in the two sexes. Clavus and base of the corium finely rastrated, 

 the apical part of the latter minutely shagreened, yellow lines of the 

 former complete at base, sometimes a little forked at both ends ; those 

 farther back are broken into two ranges, and appear more or less angu- 

 larly sigmoid ; lines of the corium forming four or five longitudinal 

 series of close, angularly sigmoid lines ; those of the membrane longer, 

 vermiculate. Tergum dull black, but the connexivum and posterior 

 margin of the segments testaceous. Venter black at base, sometimes 

 black as far as to the posterior part of the fourth segment. The ventral 

 surface is usually less marked with black in the females than in the 

 males. 



Length to tip of hemelytra, 10 millimeters ; width across the pronotum, 

 3 millimeters. 



Collected in the mountains of Colorado, by Lieutenant Carpenter, 

 July to September. 



The very acutely angular occiput, with its carina and raised edges, 



