84 



NORTH AMERICAN FAUNA. 



[No. 37. 



MARMOTA MONAX OCHRACEA Swarth. 



OCHRACEOUS WOODCHUCK. 



(PI. VI, fig. 3; PI. XII, fig. 3.) 

 Marmota ochracea Swarth, Univ. of California Pub. Zool., VII, 1911, p. 203. 



Type locality. — -Head of Fortymile Creek, Alaska. 



Distribution. — Interior mountain ranges of Yukon and northern 

 British Columbia, from Fortymile Creek south to the Babine Moun- 

 tains (and Stuart Lake?). 



Characters. — Similar to canadensis, but paler below and hairs on 

 back extensively tipped with ochraceous, the underfur more vina- 

 ceous; tail pinkish cinnamon all around; skull longer and relatively 

 narrower. 



Color. — ^Underfur of upperparts dark mouse gray at base, suc- 

 ceeded by a broad area of vinaceous-cinnamon, the latter shading 

 toward the tips into orange-cinnamon, most intense on hinder back; 

 long hairs orange-cinnamon, then blackish brown, broadly tipped 

 on fore back with ochraceous-buiT and on hinder back with light 

 ochraceous-buff ; top of head dark hair-brown; sides of nose and face 

 light ochraceous-buff ; underparts tawny shading to hazel; legs hazel; 

 feet fuscous or fuscous-black with scattering hazel hairs; tail pinkish 

 cinnamon all around, the tip clove brown. Variation: Young speci- 

 men from type locality: Darker below than adult, and feet more 

 varied with hazel. Immature specimen from Pike River, British 

 Columbia: Upperparts cinnamon (without plumbeous bases to the 

 hairs), tipped with pinkish buff; underparts cinnamon-rufous. 



STcull. ^ — ^Longer and relatively narrower than that of canadensis, 

 with narrower rostrum and interorbital region; bullae broader. 



Measurements. ^ — SJcull: Subadult (male ?) from Babine Mountains, 

 British Columbia: Condylo-basal length, 81.2; palatal length, 48; 

 postpalatal length, 30; length of nasals, 33.4; zygomatic breadth, 

 52.7; breadth across mastoids, 39.8; least interorbital breadth, 19.8; 

 breadth of rostrum, 17.2; maxillary tooth row, 20. 



Remarlcs. — ^This subspecies is the most northerly ranging member 

 of the group. It occurs west of the continental divide in Yukon 

 and northern British Columbia, but the limits of its range are not 

 known. Only six skins have been seen. A specimen from near 

 Teslin Lake, southern Yukon, is slightly darker below than the type 

 (being uniform kaiser brown) ; the fore back is darker ochraceous, 

 and the head blackish brown. Another specimen from Pike River, 

 British Columbia, is dark blackish brown all over. A series of skuUs 

 without skins from Stuart Lake, British Columbia, is provisionally 

 referred to this race. 



' No skulls from the type region available; description based on subadult specimen from Babine 

 Mountains, British Columbia. 

 2 No external measurements available. 



