460 TERTIARY INSECTS OF NORTH AMERICA. 



front of the head, the second slightly longer than the head. Thorax in mid- 

 dle a little shorter than the head, about two and a half times as broad as the 

 middle length, the posterior lialf of equal width, in front tapering rapidly by 

 the oblique straight sides, the apical nearly half as broad as the basal mar- 

 gin and roundl}^ emarginate to receive the head. Scutellum triangular, 

 with straight sides and angulated apex in no way produced, reaching half- 

 way to the ti]) of the abdomen. Hemelytra considerably surpassing the 

 abdomen. 



A single species is known. 



MaT^OSCHISTUS LIMIGENUS. 



The whole body with the antennae and legs blackish or blackish gris- 

 eous; the outer margins and sides of the head appear to be darker than the 

 central portions, the corium of the hemelytra evident!}" testaceous and the 

 membrane clear. The head appears to be smooth ; the thorax is coarsely, 

 and the scutellum very coarsely, granulate, and the corium of the hemelytra 

 faintly granulate on the basal portions like the thorax. 



Length, 14.5°"" ; breadtli of thorax, 6"'°'. 



Flori.ssant. One specimen, No. 1.1095, obtained by the Princeton Col- 

 lege Expedition. 



6. POLIOSCHISTUS gen. nov. (;roA/o?, aywr6<). 



Body with the general form of Euschistus. Head of moderate size, 

 the part in front of the eyes subquadrate, a trifle broader than the intraoc- 

 idar space, the tylum and juga of equal length, the outer angles of the lat- 

 ter a little rounded. Thorax very short, nearly or quite four times as broad 

 as the median length, the posterior part of the sides laterally produced to 

 a blunt, stout knob, increasing the width of the thorax but little, the sides 

 in front rapidly tapering with a concave curve. Scutellnm large, broad, 

 triangular, with an angulate and in no way produced apex, reaching half- 

 way or a little more than half-way to the tip of the abdomen. 



Two species are known, both from Florissant. 



Table of the species of PolioscMstus, 



Piiiictuatiou of corium relatively delicate, the punctae usually separated by nmcb more thau their own 

 diameter; hemelytra le.ss than half as long as scutellum 1. P. liijahia. 



Punctuation of corium relatively coarse, the punctie usually separated by only so much as or very littlu 

 more than their own diameter ; hemelytra more thau twice iis long as .scutellum. .2. P. laiiidariiiii. 



