voL. 1v.] Motes on a Collection of Mammals. 323 
12. <Arvicolasp.? 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. Sztomys americanus gambelit? (Baird). Gambels’ White- 
footed Mouse. 
White-footed mice were observed at ae Point, Summit 
Station, and on Mt. Tallac. A single specimen, No. 3, a male, 
taken at Red Point on June 27, is darker in Se Hla 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. 472, is pale yellowish, resembling in color 
Sitomys americanus sonortensis. 
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 
Sitomys boylit 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 boylit 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 
