6 THE ZOOLOGIST. 



Thrushes {Turdus musicus) of the Hebrides, and the Wren 

 {Troglodytes p. hirtensis, Seebohm) of St. Kilda. The Orkney 

 Vole {Microtus orcadensis) is also of a darker shade than the 

 Field-Vole (M, agrestis). It is interesting here to note that in 

 the former species the adults very closely resemble immature 

 examples of the Water- Vole. Millais mistook his species at first 

 sight for a Water-Vole (Zool. 1904, p. 241). 



There are many interesting problems connected with our 

 British fauna which are well worth consideration. Why has 

 the Lemming [Myodes norvegicus), once a British mammal, 

 become totally extinct in Britain, though it swarms in countless 

 numbers in other countries ? Its near ally, the Field- Vole, on 

 the other hand, remains with us, and often increases in such 

 overwhelming numbers as to cause " Vole plagues." Yet its 

 mortality must be enormous when we consider that it, together 

 with Field-Mice, forms the staple diet of a host of carnivorous 

 mammals and birds. 



The most important literature and synonymy at present 

 available with regard to the Jersey Vole and other Voles is as 

 follows : — 



Jersey Vole. 



Evotomys casarius, Miller, ' Annals and Magazine of Natural 

 History,' February, 1908; Bunting, 'Zoologist,' 1908, p. 462 

 (December). 



Bank-Vole. 



Microtus (Evotomys) glareolus, auctorum. 



Evotomys hercynicus hritannicus, Miller, " Preliminary Ee- 

 vision of the European Eed-backed Mice," 'Proceedings' of the 

 Washington Academy of Science, vol. xi. pp. 83-109 (1900). 



Other Species and their Allies. — Miller, " On the Genera and 

 Subgenera of Voles and Lemmings," United States Department 

 of Agriculture (Division of Ornithology and Mammalia), North 

 American Fauna, No. 12, July 23rd, 1896. 



