160 [September, 



b. Cauda pilosa. 



4. G. mexicanus, mollipilosus, saturate cinereus, supra nigro-tinctus, 

 na30 brunneo, cauda mediocri, pilosa, versus, apicem subnuda, auribus brevibus, 

 primoribus superioribus medio profunda sulcatis. 



Length from nose to foot of tail, - - - - - 11* 



" Tail, 5' 



Fore foot to end of middle claw, ----- 1-7 



Hind foot to end of middle claw, ----- 1-7 



Ascomys mexicanus Lichtenstein, Abhandl. Berl. Akad. 1825, 113 ; Brantz, 

 Muiz. 27 ; Wagner, Schreb. Saiigth. Suppl. 3, 384 ; Schinz, Syn. Mam. 2, 133. 



Saccojjhorus mexicanus Fischer, Richardson, Rep. Brit. Ass. 6, 156; Syn. Mam. 

 305 : Eydoux, Voy. Favorite, 23, tab. 8. 



One specimen, Mexico, Mr. J. Speakman. Fur very fine, shining, very dark 

 cinereous, above tipped with black, beneath entirely cinereous ; nose and whis- 

 kers brownish ; breast and fore legs slightly tinted with brown. Ears short. 

 Tipper incisors with a very deep groove on the middle of the anterior surface. 

 Feet thinly clothed with brownish hair. Tail covered with hair, which is very 

 dense and long at the base, gradually becoming shorter and more scanty, leav- 

 ing the tip almost naked. 



This specimen agrees with Lichtenstein's and Wagner's descriptions, except 

 that the tail is not " very thinly haired ; " a lighter colored specimen mentioned 

 in a marginal note by Wagner, had the " root of the tail surrounded by a very 

 short band of hair ; the remaining part naked, with verticillate scales." So that 

 this species must vary considerably in the structure of the tail, or there are 

 several closely allied species confounded under the same name. The extraordi- 

 nary variations mentioned by Brantz, but not seen by any other author, would 

 seem to give weight to the latter opinion ; the varieties are thus described : 



"/?. Castaneus, infra canescens, maculis gastrsei daabus nigro-fuscis. 



"}/. Saturate nigro-fuscus, maculis gastreei duabus irregularibus albis, canal- 

 iculo dent. prim. sup. magis laterali et externo." 



I have omitted the citations from Hernandez and other old and unsystematic 

 authors, because I see no utility in repeating continually barbarous names, which 

 were in use before natural history assumed the form of a science. 



5. G. oregonensis, mollipilosus, cinereus, castaneo-tinctus, dorso fusces- 

 cente, mento, cauda brevi, pedibusque albo-pilosis, auribus brevissimus, primo- 

 ribus superioribus bisulcatis. 



Length from nose to root of tail, 



" Tail, 



Fore foot to end of third claw, - - - 



Hind foot to end of third claw, - - - 



Two specimens marked " Pseudostoma bursarius, Columbia river, J. K. 

 Townsend." Another from Mr. Audubon without locality, under the same 

 name. Fur fine, shining, very dark cinereous, tipped with chestnut brown, 

 becoming paler beneath ; hair on the middle of the back tipped with fuscous ; 

 whiskers shorter than the head, whitish ; chin with a large spot of whitish hair ; 

 feet densely clothed with white hair. Ears with a very short elevated margin. 

 Upper incisors with a very deep groove at the middle, and a narrow but distinct 

 one at the inner margin of the anterior face. Tail short, covered with whitish 

 hair, becoming scanty at the tip. Claws of the posterior feet rather obtuse, and 

 moderately flattened. 



The hairy tail and white chin at once distinguish this species from G. cana- 

 densis. The color is much less red, and the middle of the back darker. It agrees 

 very closely with the figure and description of Diplostoma? bulbivorum, Rich- 

 ardson, Fauna Bor. Am. 206, pi. 18B, (the latter marked by mistake D. Dougla- 

 sii,) but that species has no grooves on the upper incisors. 



