VOL. IV.] Notes on a Collection of Mammals. 323 



12. Arvicola sp.? Meadow Mouse. 



Three Arvicolas, which I am at present unable to identify, 

 owing to the unsettled condition of the genus, were taken in a 

 hay field in the Carson Valley, Nevada, on August 9th. They 

 are extremely abundant in fields in some parts of the Valley, and 

 at times are very injurious to crops. 



An Arvicola, probably a different species, was noticed in 

 boggy meadows about Summit Station, on Mt. Tallac, and near 

 Pyramid Peak. These animals had well- beaten runways and 

 numerous holes, showing that a colony of several hundred lived 

 together. Once in a bog at the base of Pyramid Peak one of these 

 little animals stopped for a moment at the mouth of its burrow, 

 thus giving me time to notice its dark coloration and small size. 



13. Sitotnys americanus gambeliif (Baird). Gambels' White- 

 footed Mouse. 



White-footed mice were observed at Red Point, Summit 

 Station, and on Mt. Tallac. A single specimen, No. 3, a male, 

 taken at Red Point on June 27, is darker in coloration than any 

 of the adults from Mt. Tallac. A Sitomys, probably referable to 

 this species, was captured at Summit Station, but the specimen 

 was unfortunately lost. The series of eight specimens from Mt. 

 Tallac show great individual variation. They range from bluish 

 in the young to deep brown with a vinaceous tinge in the adults. 

 One specimen. No. 47 $ , is pale yellowish, resembling in color 

 Sitomys americamis so7ioriensis. 



This species was noticed generally in dry pine woods and 

 specimens were caught in traps baited with bits of bread and 

 dried fruit; a single specimen was secured while turning over a 

 log in search of beetles. 



There is some doubt whether this species may not be the 

 Sitoviys boy Hi of Baird, which was described from a single speci- 

 men taken by Dr. C. C Boyle in El Dorado County, on the Mid- 

 dle Fork of the American River in 1852. The description of 

 Sitomys boy Hi is imperfect and the type specimen is faded and 

 mutilated, so that it is impossible to find exactly what the char- 

 acters of that species are, as noted by Dr. Allen in his recent 

 review of some Californian Sitomys. My specimens, with one 

 exception, were all taken at a high altitude. It is not known 



