MAMMALS. 
91 
Family CASTORID^. 
Castor fiber, L. iEuropean iSeaber. 
Family MYOXIDiE. 
61. Muscardinus avellanarius, {L.) Dormouse. 
Family MURID-ffi. 
62. Mus minutus, Pallas. Harvest Mouse. 
63. Mus sylvaticus, L. Wood Mouse. 
We have only once observed this species in a birch-wood on 
the side of Loch Shin, but Selby mentions it as common so 
long ago as 1834, and it is common in the east of the 
county. 
Very common in Caithness {fide W. Eeid). 
64. Mus musculus, L. House Mouse. 
Common in both counties. 
65. Mus rattus, L. Black Rat. 
The only authentic occurrence we are able to record, is on the 
authority of Dr. Joass, who informed us that a single specimen 
was shot two miles west of Golspie in 1879, about a mile 
from the nearest houses, which would therefore be the sea- 
port of the Ferry. Unfortunately, it was too far gone for 
preservation for the Museum. We have innumerable 
records, of varying value, of the black rat from many parts 
of Scotland, the above being the only one from Sutherland. 
As the black water vole is very common, it can hardly have 
been confounded in this case. 
No reliable records from Caithness. 
