WATER VOLE. 2 



variety, in the Museum of the Edinburgh College 

 of Surgeons, the number of vertebrae is : cervica. 

 7; dorsal 13; lumbar 7; sacral 2; caudal 23 

 The intestinal canal I have generally found longer 

 in the Black than in the Brown variety ; but indivi- 

 duals of the same species often exhibit great differ- 

 ences in this respect. On the whole, however, it is 

 just as possible that there may be a Black Water 

 Vole distinct from the Brown, and even from 

 melanite varieties of it, as that we may have a Sea 

 Otter distinct from maritime individuals of the 

 Common Otter ; and, therefore, it might be well to 

 examine the subject with more care than has 

 hitherto been bestowed upon it. 



