NATURAL SCIENCES OF PHILADELPHIA. 295 



DESCRIPTIONS OF NEW SPECIES OF ORTHOPTERA. COLLECTED IN 

 NEVADA, UTAH, AND ARIZONA, BY THE EXPEDITION 

 UNDER LIEUT. GEO. M. WHEELER. 



BY CYRUS THOMAS, PH.D. 



Washington, D. C, May 9th, 1873. 

 Lieut. Geo. M. Wheeler, Dear Sir: Among the Orthnptera 

 collected by j'oiir expedition in NcA'ada, Utah, and Arizona, I find 

 several new and interesting species, and especially' tlie two follow- 

 ing, of wiiich I send the descriptions, that you may have them 

 published at as early a day as possible. 



Yours very respectfully', 

 (Signed) Cyrus Thomas. 



ACRIDIDiE. 



(EDIPODINI. 



Pedioscertetes, gen. uov. 



Back of the head ascending ; vertex rises in front of the eyes in 

 the form of a triangular pyramid ; frontal costa distinct above the 

 ocellus, fading below ; face sub-oblique. Pronotum regularly ex- 

 panding posteriorly; sub-tricarinate, the front lobes being rounded, 

 so that the lateral carinse are indistinct ; the median carina want- 

 ing, or but a minute line ; front margin truncate, hind margin 

 rounded ; the three transverse impressions distinct, but not pro- 

 found. Elytra and wings present. Posterior femora slender ; first 

 joint of the posterior tarsi as long as the other two. Metasternum 

 broad; the prosternum narrow, unspined, and without any tu- 

 bercle. Seen from above tapers considerably from the metathorax 

 to the head, which is quite narrow, but elongate perpendicularly. 



This resembles in general appearance Acrolophitus^ to which it 

 is closely allied, but from which it differs in wanting the crest on . 

 the pronotum, and in having the posterior margin of the pro- 

 notum rounded. 



P. Nevadensis, sp. nov. 



The tip of the vertex separated from the portion between the 

 eyes by a curved sulcus, which runs from the upper canthus of 

 one eye to that of the other ; this portion of the vertex is ob- 

 liquely ascending and triangular ; there are no median or lateral 

 foveolse. Frontal costa prominent and narrow between the eyes, 



