BRITISH MAMMALS 
Its favourite food consists of the juicy stems of grasses, but young shoots 
of heather and various other plants are eaten. 
The Field Vole soon becomes tame in captivity, and unlike mice and 
most other rodents seldom attempts to bite when handled. 
THE ORKNEY VOLE. 
Microtus orcadensis, Millais. 
Plate 31. 
This fine Vole, whose discovery as a distinct species we owe to 
Mr. Millais, was first described by him in the Zoologist (July 1904), 
though he had observed its distinctive features some years previously. 
The maximum size of the species, given by this naturalist in his 
Mammals of Great Britain and Ireland, is : head and body 140 milli- 
metres (51 inches), tail 30 millimetres (1^ inches), the dimensions in very 
large males being nearly double those of the Common Field Vole. 
Some living specimens in Autumn pelage I had an opportunity of 
examining were in colour a yellowish brown above, with under parts of a 
yellowish buff. Compared with the mainland Vole, this island species has 
a rounder head and much blunter muzzle and also a more bushy growth of 
the fur on the cheeks. 
Superficially it has a good deal of resemblance to the Water Vole, 
but according to Mr. Millais it is more closely related to the Common 
Field Vole. The majority of the specimens first obtained were from 
Pomona, the main island of the Orkneys, but the species has been found 
inhabiting all the larger islands of the group, except Hoy. 
It frequents the grass and clover fields on the lower parts of the islands 
and prefers moist localities. Black varieties of the species are not uncommon. 
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