296 University of Calif ornia Publications in Zoology [Vol.12 



Sierra Nevada Mountains, but it differs materially from the latter 

 both in certain cranial characters and in its golden coloration. In the 

 latter respect, however, it closely resembles the small Aplodontia phaea 

 Merriam, found in Marin County, California. Specimens taken on 

 the slopes of Mount Shasta seem to be typical of A. calif omica, show- 

 ing no gradation towards A. chryseola. 



The general coloration of Aplodontia chryseola, on the back, is 

 fulvous or ochraceous, thickly sprinkled with black. The dense under- 

 fur is black at the base in fresh pelage, wearing to slate, and tipped 

 with ochraceous-buff. The long hair is a mixture of gleaming 

 ochraceous-buff and black, giving a peculiar bright effect, of gold and 

 black. The sides are ochraceous-buff with fewer black hairs. The 

 underparts are plumbeous, wearing to lighter gray, and heavily 

 sprinkled with ochraceous-buff, especially around the throat and 

 cheeks. The tip of the nose is seal brown, face drab, whiskers mainly 

 white. 



A further discussion of the Trinity mountain beaver, as well as an 

 account of its habits, is contained in the writer's paper on the mam- 

 mals of the Trinity Mountain region now in preparation. In order 

 to facilitate further work on the Aplodontiidae, in progress both in 

 the Department of Palaeontology and in the Museum of Vertebrate 

 Zoology, of the University of California, immediate publication of 

 this description is deemed advisable. 



Transmitted January 24, 1914. 



