PREVIOUS WORK 



b. Previous Work and Present Treatment. 



Modern knowledge of the Microtinse is based upon Miller's 

 " Genera and Subgenera of Voles and Lemmings," published in 

 1896.^ In that fine work Miller gave an admirable review of the 

 earlier classifications and established a natural classification which 

 swept away the more or less artificial systems of his predecessors 

 (de Selys-Longchamps 1836-1862, Blasius 1857, Baird 1857, 

 Fatio 1867, Coues 1874, Blanford 1881, Lataste 1887). Subsequent 

 research has tended only to extend and to correct in detail the 

 results at which Miller arrived. 



Miller confined his attention chiefly to the living members of 

 the subfamily, of which he recognized seven genera, namely, 

 Synaptomys, Lemmus, Dicrosto)>yx, Phenacomys, Evotomys, 

 Microtus and Fiber [= Ondatra]. Synaptomys included two 

 subgenera, Synaptomys and Mictomys, as in the present work ; 

 whereas Microtus included eleven subgenera, namely, Eothenomys, 

 Anteliomys, Lagurus, Alticola, Hyperacrius, Pedomys, Phaiomys, 

 Pitymys, Chilotus, Microtus, Arvicola, andNeofiber, all of which are 

 now accorded full generic rank. Ellobius, here included in the 

 Microtinse, was not regarded as a member of the subfamily. 



Miller's work both stimulated and facilitated further research, 

 so that in current literature more than fifty genera and subgenera 

 (including fossil forms) are recognized. But some of these are 

 not valid, and here only thirty-one genera and subgenera are 

 described. 



The most important recent addition to our knowledge con- 

 cerns the remarkable genus Prometheomys described in 1901 by 

 Satunin. Vinogradov has prepared a valuable and beautifully 

 illustrated account of some material now in Leningrad ; that 

 paper, to which I am greatly indebted, will be published elsewhere. 

 My knowledge of the genus rests, however, upon an even more 

 solid foundation, thanks to the Hon. Ivor Montagu, who visited 

 the Caucasus in the interests of the British Museum last autumn. 

 There he obtained a magnificent series of specimens representing 

 all the stages of growth of this rare animal; this material 

 has enabled me to reach a definite conclusion as to the relationship 

 of the genus and substantially to confirm Vinogradov's results. 



As regards living species my work has been greatly lessened 

 by the labours of Miller and Thomas in the Old World ; and by 

 those of Bailey, HoUister and many others in America. The 

 collection of North American Microtinaj in the British Museum, 

 although sufficient to enable one to appreciate generic characters 

 and those of some of the leading species, is far too small and 

 incomplete to warrant any attempt being made to give an inde- 

 pendent and new account of American species and subspecies. 

 But revisions of the North American species of Evotomys and 



' North American Fauna, No. 12, 1896. 



