new European Voles. 199 



Pajares, Leon, Spain, June 23, 1907, by Norberto Gonzalez. 

 Orio^inal number 321. 



Characters. — Larger than Microtus arvalis, the skull 

 massive and deep, with strongly convex dorsal profile, 

 widely spreadini^ zygomata, short, broad brain-case, strongly 

 ridged interorbital region, and very large audital bullae; 

 teeth as in M. arvalls ; colour about as in the more bufFy 

 forms of M. arva/is (upperparts biifFy clay-colour, rather 

 coarsely " lined " with black along median dorsal area, clearer 

 and more nearly approaching ochraceous-biiff on sides ; under- 

 parts dull grey, clear or wa.shed with light i;ufF; feet an 

 indefinite bufFy grey tinged with drab, not conspicuously 

 different from colour of back ; tail obscurely bicolor, buffy 

 grey below, brownish mixed with grey above). 



Measurements. — Type. Head and body 120 mm.; tail 37 ; 

 hind foot 20*; ear 14. Skull : condylo-basal length, 26*2; 

 zygomatic breadth 15"2 ; distance from interorbital con- 

 striction to back of condyle 15 ; interorbital constriction 3 2; 

 occipital breadth 12'2 ; occipital depth (median) G"4 ; palatal 

 depth 8*6 ; na-al7-8; diastema 7*8 ; mandible 16*6 ; maxil- 

 lary tooth-row 6-6 ; mandibular tooth-row 6*4. 



Specimens examined. — Three, all from the type locality. 



Remarks. — In its large, massive skull Microtus asturianus 

 differs conspicuously from its nearest geographical ally, 

 M. arvalis meridianus of the Basses- Pyrenees region. Its 

 strongly convex dorsal outline gives the skull a superficial 

 resemblance to that of M. cahrera of the Sierra de Guadar- 

 rama, but the nasal bones are strictly of the arvalis type. 

 The size and massiveness of the skull are so great as to 

 suggest a small Microtus orcadensis, but it is scarcely probable 

 that any direct relationship is indicated by this resemblance. 



Microtus sandayensis westra;, subsp. n. 



Type.—M\x\i male (skin and skull). B.M. no. 8. 1. 2. 1. 

 Collected at Puriswall, Westray, North Orkney Islands, 

 April 5, 190G, by Norman B. Kinnear, Esq. Original 

 number 290. Presented by the collector. 



Characters. — Size and cranial characters as in }[icrotus 

 sandayensis sandayensis (Millais), but first lower molar with 

 anterior outer re-entrant angle occasionally (in 2 specimens 

 among 6) as well developed as in M. orcadensis ; colour not 

 so pale as in the Sanday vole, the underparts strongly washed 

 vvitli yellowish brown (general effect above a dark hair-brown 



* CoUector'a measurement. In the pro])arfd i^peciini'n the liind foot 

 (slightly distorted) after rclaxinf^ measiuvs 19-1 mm. 



