458 TEKTIARY INSECTS OF NORTQ AMERICA. 



Thnetoschistus revulsus. 



PI. 28, Fig. 6. 



Whole body griseous, the juga apparently lighter than the tylum, the 

 membrane faintly infumated. Head faintly, shallowly, and coarsely punc- 

 tate ; thorax distinctly, rather sparsely, and coarsely punctate ; scutellum 

 still more coai'sely punctate, but otherwise similar ; corinin of hemelytra 

 punctate like the thorax, but less coarsely and less sparsel}'. 



Length, 14.5°"" ; breadth of base of thorax, 6.5"". 



Plorissant. One specimen, No. 1.837, collected by the Princeton 

 Expedition. 



;5. POTESCHISTUS gen. nov. (ttots. oxiord?). 



Remarkable for the regularly ovate form of tlie l»ody. [Head unfortu- 

 nately wanting.] Thorax more or less broken and crushed, so as to render 

 its precise form indeterminable, but apparently it was uniformly vaulted, 

 nearly twice as bi'oad as long, tapering from the very base with no lateral 

 projections, the sides arcuate and tapering pretty regularly, the outer 

 anterior angles well rounded, the apical margin less than half the width of 

 the base, gently and regularly emarginate for the reception of the head. 

 Scutellum triangular, as long as broad by reason of the arcuation at the 

 base of the otherwise straight sides, the tip angulate, not in tlie least rounded 

 or produced, reaching barely half-way to the tip of the somewhat conical 

 abdomen, which the hemelytra surpass a little. 



A single species is known. 



POTESCHISTUS OBNUBILUS. 

 PI. 28, Fig. 18. 



The thorax is smooth except for an exceedingly sparse, low, and incon- 

 spicuous granulation. Scutellum, on the contrary, very coarsely granulate 

 indeed and less sparsely ; the hemelytra midway between the two and 

 tolerably dense ; membranal suture with a barely perceptible arcuation 

 opening outward, and the otherwise clear but faintl} veined membrane 

 coriaceous at its extreme inner base, between the membranal suture and the 

 end of the claval suture. Whole body brownish griseous, the scutellum 

 liglite)". 



Length, excluding head, 13.75'""; breadth, 7.5°"°. 



Florissant. One specimen, No. 1472. 



