1913] Grinnellr-Swarth : Birds and Mammals of San Jacinto 353 



The Strawberry Valley and Ilemet Lake scries arc to all 

 appearances identical in color and size with topotypes of nigri- 

 cans. Unfortunately our scries does not include old males. In 

 the females, however, the skulls are distinctly lighter, with 

 narrower brain-case, and less squarish zygomae than in topotypes 

 of nigricans. The example from Thomas Mountain is unequiv- 

 ocally nigricans like those from Ilemet Lake. The two Ken 

 worthy gophers are very young. The only specimen from Santa 

 Rosa .Mountain, is a male, young adult, satisfactorily referred to 

 nigricans from both cranial and external characters. The Ful- 

 ler's Mill specimen is a male, young adult; in color it strongly 

 resembles altivalUs, bul its skull is altogether too light for thai 

 species, and together with general measurements, coincides with 

 nigricans. It is to be borne in mind, too, that the color differ- 

 ences between nigricans and altivalUs are slight. The same 

 remarks apply to the four examples from Schain's Ranch. 



The conspicuous features of nigricans, as represented in the 

 San Jacinto region, are xrrx small size (see tables), very dark 

 reddish brown colors, and light skulls with small audital bullae. 



We cannot see the logic in calling nigricans a subspecies of 

 fiilrns, as it has heretofore been considered, even granting the 

 close similarity; for, in addition to the fad that a broad area 

 inhabited by unrelated forms intervenes between the ranges of 

 the two. there is the further circumstance that nigricans and 

 fnlvns occupy different life zones. These geographic consider- 

 ations should be given weight in settling the status of forms. 

 There is no continuity of range, and no intergradation possible. 



All through the region including the specified localities of 

 capture, signs of gophers were plentiful. The evident inactivity 

 of adults after the breeding season probably accounts for our 

 failure to secure good old examples. 



