VOLES. 217 



long and thick, usually of a uniform greyish-brown, with a 

 more or less distinct reddish tinge, but not unfrequently wholly 

 black. First upper molar tooth with five, and the second and 

 third with four, prismatic spaces ; in the lower jaw, the first 

 molar has seven such spaces (of which the first three are 

 generally imperfectly separated), the second five, and the third 

 three. Length of head and body about S^ inches ; of tail 4^ 

 inches. 



The Water- Vole, or, as it is generally incorrectly termed, the 

 Water- Rat, is a member of the sub-genus Paludicola (as defined 

 by the number of prisms in the molar teeth), and may be 

 compared to the Brown Rat in point of size. As in the case of 

 the so-called Irish Rat, the black, or melanistic variety, which is 

 as common in many parts of Scotland as it is in the Cambridge- 

 shire fens and in Norfolk, was at first regarded as a distinct 

 species, under the name of Arvicola ater. 



The Water-Vole has the body full ; the neck very short ; 

 the head short, broad, rounded, and convex above ; the limbs 

 small ; and the tail rather long and slender. The short and 

 rounded ears are entirely concealed among the thick fur, and 

 are naked internally, and thinly covered with soft hairs exter- 

 nally ; the aperture of the internal ear being capable of being 

 closed by an operculum. On the fore-feet the claws are 

 greatly compressed, but in the hind-limbs are longer ; while in 

 neither are the toes webbed. The tail is cylindrical and 

 slightly tapering, somewhat compressed towards the tip, and 

 covered with short closely-adherent hairs. The fur is composed 

 of two kinds of haiis, some being longer and a little thicker 

 than the others. At the base all the hairs are bluish-black on 

 the upper-parts, and bluish-grey below. The incisor teeth are 

 brownish-yellow, the eyes black, the nose dusky, the soles of 

 the feet pale flesh-colour, and the claws, according to Mr. de 

 Winton, are "purple, as if dyed with black-currant juice." 



