BRITISH ARVICOL^E, OR VOLES. 97 



the creature is so frequently immersed, mingled 

 with long shining hair, which gives a peculiarly 

 glossy appearance to the back and sides. The 

 incisor teeth are very large and strong, and are 

 covered externally with a layer of hard yellow 

 enamel. Though so thoroughly aquatic an animal 

 in its habits, I am convinced that the water-vole is 

 often killed in considerable numbers by colonies of 

 the house-rat, which, in the summer months, 

 migrate from the farm buildings and yards to the 

 banks of streams and ponds, committing great 

 havoc among the younger fish and water-fowl, the 

 blame of which devastation is generally placed to 

 the credit of the poor vegetarian vole. 



As I have mentioned before, the common rat is 

 as much at home by the water-side as the vole., and 

 I have seen one of the latter pursued by a rat in the 

 water, and vainly endeavouring to rid itself of its 

 enemy by continued diving. The water-vole usually 

 selects river-banks or the neighbourhood of large 

 ponds, where its favourite food, the JSquisetum, or 

 " mare's tail," grows. In these situations it forms 

 long and winding burrows, which invariably have 

 one outlet above the water and another beneath the 

 surface, so that, in case of danger, it has more than 

 one opportunity for escape. It never enters houses 

 or barns, and shuns the vicinity of man, being a 

 peculiarly shy animal. Its habits, however, are 



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