428 GEOLOGICAL SUKVEY OF THE TERRITOEIES. 



family, at others to tliose inferior to the family. I have followed the 

 former method in the present report, but do this provisionally. 



In regard to the terminology, I have only to remark that for families 

 I adopt iDiE ; for snb-families, IN^ ; and for the inferior groups, INI, 

 thereby conforming to what appears to be the prevailing usage in other 

 departments of zoology. I mention this, as by the termination I indi- 

 cate the comparative value I attach to the group. In the LocusUdw I 

 have adopted, for tlie present, the divisions of Walker, although I think 

 his system defective ; but I use them only as groups subordinate to 

 sub-families and not as equivalents. The Acrididce of the United States 

 I am disposed to divide into but two sub-families, as follows : 



I. Sub-fam. Acridiuae : 



First group, Truxalini. 

 Second group, Conophorini.* 

 Third group, Acridini 

 Fourth group, (Edipodini. 



II. Sub-fam. Tettigiuce. 



The number of species of saltatorial Ortlioptera found in that part of 

 the United States west of Iowa, Missouri, and Arkansas, which have, 

 been described, including the new species described for the first time in 

 this report, is 101. These are distributed among the different families 

 as follows: Gri/llidw, 7; Lociistidce, 33 -, Acrididw, 61. 



GryllidyE. 



Gryllus 5 species. 



;Nemobius 1 species. 



Oecanthus 1 species. 



LOCUSTIDJS. 



First group, Stcnojyehnatini. 

 Stenopelmatus 3 species. 



Second group, RapliidopliorinL 



Ceuthophilus e 7 species. 



Udeopsylla 1 species. 



i:>aihinia 1 species. 



Tropidischia .^ 1 species. 



Third group, Bradyporini, 

 Anabrus 4 species. 



Fourth group, Xocifs^iwi. 



Pterolepis (?) 3 species. 



Cyphoderris 1 species. 



Thamnotrizon 1 species. 



Decticus (?) 2 species. 



Orchelimum 1 species. 



Xiphidium 1 species. 



Locusta 2 species. 



* This name is used temporarily to embrace Mr. Scudder's sub-families, Xiphocereace 

 and Fccciloccridce. 



