350 MICROTIN^ 



agrestis groups. Other characters sufficiently described under 

 the genus. 



Measurements (according to Mehely).— Length of the upper 

 and lower tooth-rows ()n}-m^) measured on the grinding surface, 

 6-3 mm. Individual teeth : m\ 2-5; nfi,2-l; w^l•7; m^, 2-9; 

 ^2, 1'8; m3, 1-6. 



jGenus : 13. MIMOMYS Forsyth Major. 

 1846. Arvicola Owen, Brit. Foss. Manim., p. 205 (remains from Pliocene 



of Norfolk and Suffolk indicating a species intermediate in size 



between "^. amphibia" and " /i. arvalis"); Blackmore and 



Alston, P.Z.S., 1874, p. 462 (in part). 

 1872. Arvicola Forsyth Major, Atti Soc. Ital. Sci. Nat., 15, p. 389 



(jaws with rooted molars from the Upper PUocene lignite of 



Leffe, Lombardy). 

 1882. Arvicola [Evolomys) Newton, Vert. Forest Bed, p. 83 (British 



Pliocene forms with rooted molars referred to subgenus Evolomys). 

 1894. Pheriacomys Nehring, Naturwiss. Wochenschr., 1894, No. 28, 



(forms with rooted molars from Beremend, Hungary, together 



with those from the British and Italian Pliocene, referred to 



Phenacomys Merriam). Not of Merriam; see Miller, N. Amer. 



Fauna, No. 12, 1896, p. 75. 

 1898. Dolomys Nehring, Zool. Anz., 1898, p. 13 (in part). Genus 



based upon one of the species occurring at Beremend, Hungary 



(D. milleri), and supposed to be congeneric with the British and 



Italian forms. 

 1902. Mimomys Forsyth Major, P.Z.S., 1902, 1, p. 102; genus for 



all those voles " with rooted molars, which are clearly different 



from Evolomys, Phenacomys and Dolomys.'''' Recognized three 



species from the Pliocene of Britain and Italy. 

 1902. Microtus Hinton and White, Proc. Geol. Assoc, 17, p. 414; 



referred a rooted molar from Early Pleistocene (High Terrace) of 



the Thames Valley to " Microtus intermedins Newton." 

 1908. Microtus (Mimomys) Newton, Bull. Soc. Beige de Geol. Mem., 



21, p. 592; Riitten, Die cUluviale Siiugethiere der Niederlande, 



1908-10, p. 88; remains from Holland and Belgium referred to 



subgenus Mimomys. 

 1910. Mimomys Hinton, Proc. Geol. Assoc, 21, p. 491 (genus); 



Mehely, Ann. Mus. Nat. Hungar., 12, 1914, p. 185. i 



1914. Microtomys Mehely, Ann. Mus. Nat. Hungar., 12, p. 209. 



Genotype. — Mimomys pUoccBnicus Forsyth Major; formally! 

 selected by Mehely (Ann. Mus. Nat. Hungar., 12, 1914, 1 

 p. 185). 



History. — The essential details relating to the history of this ] 

 important genus are given in the notes intercalated in the ! 

 synonymy above. For many years after the first discovery of 

 its remains in the British Pliocene, species of the genus, on 

 account of the great superficial likeness of their teeth to those 

 of the Water Vole, were referred to Arvicola amphibius. In 

 1872 Forsyth Major found that the cheek-teeth of some speci- 



