GEOLOGICAL SURVEY OF THE TERRITOEIES. 439 



purpurascens. I had not tlien seen a specimen of A. simplex j Halcl. ; nor 

 had I seen the excellent synopsis of the Earo])eau species of Thamno- 

 trizon by Brunner de* Wattenwyl, (in Yerhandl. Zool.-Bot. Yereins in 

 Wien, XI, 1861,) the articles by Yersin, (Ann. Soc. Eot. Franc, 3d ser., 

 Tom. YI and Yll,) or Fieber's Synopsis, (Lotos, 1853.) I^ow, having 

 specimens of all the species {simplex^ Haldemannii^ purpurascens) before 

 me, and access to the works named and those of Serville, Fischer, &c., I 

 find that while I was correct in separating the species, I was mistaken 

 in the disposition made of them, and, as a matter of conrse, in my 

 emendation of the generic characters. 



The genus Anahrus was formed by Haldeman for the reception of his 

 A. simplex^ hence in emending the original description its characters 

 should be such as to embrace the species on wliich it was founded. A 

 more thorough examination of the generic characters of Thamnotrizon 

 as given by the various authors; a comparison of the figures by Brun- 

 ner de Wattenwyl,Yon Frauenfeld, Fischer, &c., and personal inspection 

 of some specimens which I am satisfied belong to this genus, discovered 

 the past season, lead me to the conclusion that the arrangement and 

 number of spines on the front of the anterior tibi^ is a true normal 

 character, although having some slight exceptions, (for T. fallax appears 

 from the figure in Yerhandl. Zool.-Bot., XI, 1801, PI. 10, to Yary from 

 this type.) As A. simplex and purpurascens have two rows of spines on 

 the front of the anterior tibiae, (one 4-5, the other 2-3, making in all C-8,) 

 they cannot belong to this genus, but should remain v/here originally 

 placed. A. Haldemannii^ having the prosternum very distinctly bispinose, 

 must be placed in some other genus, and even without thi*s distinction 

 there are other differences which will remove it from generic association 

 with these species. I am not well satisfied where it should go, but place 

 it provisionally in Fterolepis^ Fisch., (not Serville,) with which it appears 

 to be most nearly allied. 



There is much confusion in regard to this group of genera. Fischer 

 (Orthop. Euroi).) separates Thamnotrizon from Fterolepis of Eambur, 

 I)lacing the species without prosternal spines in the former, leaving 

 those with spines in the latter ; while Serville places the species without 

 prosternal spines in Fterolepis. Fieber, following Serville, places the 

 unarmed species in Fterolepis and forms a new genus — Ehacocleis — for 

 those which are spined. Yersin (Ann. Soc. Eut. Franc, 3d ser., YI) 

 describing Fterolepis alpina gives the spines as a character. Orcliesticus 

 of Saussure (Eev. Mag. ZooL, 2d ser., XL, 1859, p. 201) comes very close 

 to this, the chief difference being in the mesosternum. Brunner de 

 Wattenwyl appears to follow Fischer in regard to Thamnotrizon, but 

 on the other hand adopts the Ehacocleis of Fieber for his spined species, 

 omitting Fterolepis altogether. He forms a sub-genus in Fecticus, 

 which he names Fsorodonotus^ to which he removes Fterolepis aJpina^ 

 Yersin. 



In the midst of such confusion, which Walker has increased by the 

 formation of several too closely- allied genera, it is difficult to place a 

 somewhat abnormal species. It is probable 13r. Scudder will clear up 

 this difficulty in his anxiously looked-for work on the Orthoptera ; there- 

 fore for the present I have adopted the following arrangement as the 

 best I can do with the materials I have at hand. I would not venture 

 to take this step if it were not necessary to adopt some consistent ar- 

 rangement of the new species I obtained during my recent visits to the 

 Eocky Mountains. 



Discarding Ehacocleis, Fieb. ; retaining Fterolepis, Fisch., (Not. Serv. ;) 

 and restricting the other genera to their true limits, the genus Anahrus 



