398 BULLETIN UNITED STATES GEOLOGICAL SURVEY. 



preaching the head, auteriorly a little curved ; the anterior angles a 

 little rounded. Pectus deep black, polished, coarsely punctured on the 

 disks of the areas ; the odoriferous apparatus dull black. Legs piceous- 

 black; the outer face of all the tibiae with an abbreviated white streak; 

 the bristles yellowish; tarsi piceous. Scutellum polished, remotely, 

 coarsely punctured on the middle, each side, and some transverse series 

 posteriorly confluently punctured; frenum and extreme tip piceous, the 

 latter a little impressed, broadly rounded. Corium coarsely, regularly 

 punctured, the punctures a little more remote and shallow on the pos- 

 terior part of disk ; the costal margin white ; near the outer angle is a 

 sublunate, smooth, white spot; posterior margin subtruncate, faintly 

 sinuated adjoining the inner angle; membrane brown, the base running 

 toward the inner angle thickened ; the nervures numbering about five, 

 sometimes two of them are forked at tip. Venter polished, moderately 

 convex, densely, finely punctured each side and behind, including the 

 depressed submargin of the connexivum ; the disk impunctured ; the edge 

 of the connexivum smooth, white as far as the third segment, sometimes 

 white all the way to the base. 



Length 5-7 millimeters. Width of base of pronotum 2J-3J millimeters. 



Hab. — Almost all of the United States, as also Canada and Mexico. 



Specimens occur with no spots on the corium, with the spots reduced 

 to mere points, or with a spot only on one wing-cover. 



Hundreds of specimens of these insects have passed through my hands, 

 and I have thus had abundant materials for work in this species. The 

 result of these examinations induces me to believe that we have only 

 thus far discovered one species in Korth America. 



The males usually have a smaller emargination between the lobes of 

 the head, although the form of these parts varies in both sexes. The 

 males are most frequently destitute of the white spots of the hemelytra, 

 but occasionally the females also lack them. 



Subfamily ASOPIN^. 



Peeillus Stal. 

 P. claudus. 



Pentatoma elauda Say, Journ. Acad. Phila., iv, 312, No. 2. 



One specimen from the vicinity of Colorado Springs ; also a few 

 from the region near Denver, collected by Mr. B. ET. Smith. The pale 

 variety is the one thus far found most common in Eastern Colorado. 

 In the darker specimens, the ground-color is a rich red, and the black 

 markings are often tinged with violet and indigo. 



Evidently, the pale variety would be better protected by its agreement 

 with the sand-color of the plains on which it occurs, and perhaps 

 this is the reason why it is so much more abundant in such places. 

 The darker variety would be better protected in the red surfaces of 

 the Triassic regions, and in places where the soil is stained by oxides of 

 iron. Its enemies, such as the Phrynosonia, the various species of 



