MICROTUS. 77 



Type locality. East side of Montague Island, Prince William 

 Sound, Alaska. 



Genl. Char. Size large; similar in color to M. yakutatensis. Skull 

 large and heavy; zygomata deeply notched anteriorly. 



Color. Upperparts raw-umber, color produced by a mixture of 

 cinnamon and dusky; pectoral and inguinal regions grayish; rest of 

 underparts clay-color; head and flanks like back; tail above dark 

 brown, beneath whitish; hands dusky brown, edges whitish gray; 

 feet grayish white at base, dusky brown apically. Ex type in United 

 States National Museum. 



Measurements. Total length, 201; tail, 40; hind foot, 23.5. 

 Skull: Occipito-nasal length, 31; Hensel, 29; zygomatic width, 18.6; 

 intertemporal width 3.9; length of nasals, 9.2; length of upper molar 

 series, 7.4; length of mandible, 18.3; length of lower molar series, 7. 

 Ex type in United States National Museum. 



Microtus mordax bernardinus Merriam. 



Microtus mordax bernardinus Merr., Proc. Biol. Soc. Wash., XXI, 

 1908, p. 145. 



Type locality. Dry Lake, San Bernardino Mountains, California. 

 Altitude, 9000 feet. 



Genl. Char. Similar to M. mordax in general appearance. Skull 

 heavier; nasals longer and broader; zygomatic arches wider, and 

 zygomatic processes more developed. 



Color. Upperparts snuff -brown; tips of hairs buffy; cheeks gray; 

 flanks pale grayish brown mixed with buffy; underparts grayish 

 white, plumbeous under-fur showing; tail brown above, whitish 

 beneath; hands dusky, feet pale brown. Ex type in United States 

 National Museum. 



Measurements. Total length, 1 80; tail, 56; hind foot, 21. Skull: 

 Occipito-nasal length, 26.5; Hensel, 23.3; zygomatic width, 15.3; 

 length of nasals, 7.7; palatal length, 6; length of upper molar series, 

 6.3; length of mandible, 15.2; length of lower molar series, 9.2. Ex 

 type in United States National Museum. 



Microtus provectus Bangs. 



Microtus provectus Bangs, Proc. N. Engl. Zool. Club, IV, 1908, 

 p. 19. 



Type locality. Block Island, Rhode Island. 



Genl. Char. Larger than M. pennsylvanicus, belly gray. Skull 

 longer than narrower. 



Color. Upperparts yellow-bistre, some hairs with dusky brown 

 tips; underparts gray; middle of belly and between arms whitish; 

 hands and feet dusky brown; tail above dusky, beneath grayish. 



