258 University of California Publications in Zoologij. [Vol. 7 



In the present state of our Imowledge of the mammalogy of the 

 Great Basin the present disposition seems to be the most appro- 

 priate, since it is impossible with the data at hand to determine 

 definitely its relation to any of the neighboring species. 



Thomomys fuscus fisheri (C. H. IMerriam). 

 Fisher Pocket Gopher. 



Status. — A comparison of our gophers with a series of six 

 specimens of fisheri from the collection of the United States 

 Biological Survey, four being topotypes from Beckwith, Sierra 

 Valley, Plumas County, California, and two being specimens 

 taken at Reno, Nevada, shows them to be this form. In his 

 description of the subspecies Merriam (1901, p. Ill) gives the 

 following average measurements of six specimens from the type 

 locality: total length, 192 nun. ; tail vertebrae, 58; hind foot, 25. 

 It will be seen from the appended table that our animals vary 

 little from these figures. 



The series collected by us was captured during June and 

 July. The specimens at hand from Beckwith and Reno are 

 August and October animals. All the adult specimens taken by 

 our pjxpedition show definite molt lines. In two of them (nos. 

 7848, 7852) the molt is about half completed, while in three 

 others (nos. 7850, 7851, 7853) it is three-quarters done. These 

 last were taken in July, the first two in June and early in July 

 respectively. The Biological Survey specimens, with the excep- 

 tion of three (nos. 101240, 101245, 134853) have the new pelage 

 complete. The two series are much the same in color, the only 

 apparent difference being in the color of the throat, which is 

 pure white in the specimens from Beckwith and Reno, and light 

 gray in the Pine Forest ^lountain series. There is a i)ossil)ility, 

 however, that this color in the latter is due to the soil in which 

 they live, or to a difference in pelage i)rogress. The last is the 

 most probable explanation, as the hair on the throat of each l*ine 

 Forest ]\Iountain example is thinner and shorlcr llian Ihat on 

 the topotypes. Over against tliis, however, is tlie fact that on the 

 Beckwith and Reno animals the entire hair on the throat is 

 white, having no gray or ])lunibe()us ])ase, and so ai)pai'('ntly 



