Recent Voles of the Microtus nivalis Group. 99 



molar ; posterior border of palate with median ridge usually 

 flattened and ill-defined, its width at least equal to that of 

 shallow lateral pit. Colour smoke-grey above, strongly 

 washed with bister on back, and usually tinged with pale 

 buff along sides ; underparts dull white, irregularly clouded 

 by the slaty under-colour; feet and tail whitish, the tail 

 usually (in about two-thirds of the skins examined) tinged 

 with brown above, but apparently never sharply bicolor. 



Microtus nivalis nivalis (Martins). 



1842. Arvicola nivalis, Martins, llevue Zoologique, p. 331. (Faul- 

 horn, Switzerland.) 



1843. Arvicola a/pinus, Wagner, Schreb. Saugth., Suppl. iii. p. 570. 

 (Andermatt, Switzerland.) 



184.5. Arvicola nivicola, Schinz, Synops. Mamni. ii. p. 236. (Highest 



Swiss Alps; probably near Andermatt.) 

 ISoS. Hypudceus petrophilus, Wagner, Mlinch. Gelebrt. Anzeiger, 



p^ 307 (March 28, 1853). (Obersdorf, near Sonthofen, Allgau, 



bavaria.) 



Type locality. — Faulhorn, Switzerland. 



Geograpliical distribution. — Alps, Apennines, and Tyrol. 

 (Probably includes more than one geographical race.) 



Characters. — Anterior loop of tirst lower molar tending 

 to assume an arrow-head-like outline, owing partly to the 

 general narrowness of the loop, but more especially to the 

 form of the postero-external salient angle, which is usually 

 narrow and sharply pointed, and rarely if ever * obsolete. 



Remarks. — The form of the anterior loop of the first lower 

 molar appears to be characteristic of the Alpine race of 

 Microtus nivalis, as the specimens that I have examined 

 are immediately recognizable by this character alone. In 

 two skulls from the type locality of Hypudceus petrophilus, 

 kindly placed at my disposal by Dr. C. I. Forsyth Major, 

 and in the single specimen in the British Museum from the 

 Apennines t (Mt. Cimone, collected by Dr. jNIajor), this 

 loop is of the broadly crescentic form characteristic of the 

 Pyrencau race. The Mt. Cimone specimen also appears to 

 have the rostrum unusually robust. The material is, how- 

 ever, iiisulHcicnt for satisfactorily determining the exact 

 status oi' /jetrop/rilus and the Apcnnine animal. 



Microtus nivalis uquitanius^ subsp. n. 

 Type. — Young adult male (skin and skull) collected near 



* Never in the material thus far examined. 



t See also the ligures of Apennine specimens published by Ilinton, 

 rroc. Geol. Assoc, x.v. pt. 2, pi. i. tigs. 1-4 (1907). 



7* 



