22 LAKES AND RIVERS. 



banks of canals. Like other species of rats and 

 mice, this vole is sometimes found as an albino. 

 Mr. Macgillivray describes a variety of it which is 

 black, and which he names Arvicola ater. He at 

 one time thought it a distinct species, but afterwards 

 seemed undecided about this, the skeletons being 

 similar, as well as the fur, except in colour. The 

 chief difference, he says, is in the size of the skull, as 

 the black variety is generally smaller than the brown. 

 Similar differences,however,frequently occur in animals 

 of undoubtedly the same species. 



Early in the spring of 1855, I dug out the burrow 

 of a water-vole, and was surprised to find at the further 

 extremity a cavity of about a foot in diameter, con- 

 taining a quantity of fragments of carrots and pota- 

 toes, sufficient to fill a peck measure. This was un- 

 doubtedly its winter store of provisions. This food 

 had been gathered from a large potato and carrot- 

 bed in the vicinity. On pointing out my discovery to 

 the owner of the garden, he said his losses had been 

 that winter very serious, owing to the ravages of these 

 animals, and said he had brought both dogs and cats 

 down to the stream to hunt for them, but they were 

 too wary to be often caught. White, of Selborne, 

 says : " As a neighbour was lately ploughing in a dry, 

 chalky field far removed from any water, he turned 

 out a water-rat that was curiously laid up in an hyber- 

 naculum, artificially formed of grass and leaves. At 

 one burrow lay above a gallon of potatoes, regularly 

 stowed, on which it was to have supported itself for 

 the winter. But the difficulty with me is how this 

 amphibius mus came to fix its winter station at such 



