122 



KOETH AMERICAN FAUKA. 



[no. 39. 



Distribution. — Sierra Nevada of California and Nevada, from Lassen 

 Peak south to Mammoth Pass (fig. 5). 



Cliaracters. — Size small; feet and claws very slender; ears large, 

 thin, well formed, and pointed; skull long and slender, with anteriorly 

 converging lateral ridges; colors dull hazel above, buffy below; mam- 

 mae in 4 pairs, inguinal 2-2, pectoral 2-2. 



Color. — Winter i)elage: Upperparts dull hazel with blackish ear 

 patch and plumbeous nose; underparts and feet dull buffy; tail whit- 

 ish throughout or dusky above at base. Summer pelage: Slightly 

 clearer, brighter tawny. Young, somewhat paler, more yellowish 

 than adults. 



ShuU. — Long, slender, and low; rostrum slender, especially in pro- 

 file, abruptly arched anterior to molars ; zygomata very slender ; inter- 

 parietal usually transversely oval, wider than long; nasals long, slen- 

 der, and slightly emarginate or doubly rounded at posterior tips, 

 reaching near tips of premaxillae; bullae very small; lateral pits of 

 palate deep. Dentition light; upper incisors abruptly decurved at 

 right angles to axis of skull, not protruding beyond tip of nasals, and 

 distinctly grooved. 



Measurements. — Average of 5 adult males from Emerald Bay, near 

 type locality: Total length, 212; tail vertebrae, 70; hind foot, 27.4. 

 Average of 5 adult females: 209, 67, 26.4. SJcull (of type, from original 

 description): Basilar length, 34; greatest breadth, 22; i?iterorbital 

 breadth, 6; nasals, 14. Skull (of topotype, d ad.) :^ Basal length, 32; 

 nasals, 12.5; zygomatic breadth, 20; mastoid breadth, 17; interor- 

 bital breadth, 6.2; alveolar length of upper molar series, 7. 



Remarks. — While most nearly related to the fuscus and fossor 

 groups, monticola and the other subspecies, mazama, pinetorum, nasicus, 

 and helleri, form a well-defined group. The typical subspecies appears 

 to overlap the range oi JisJieri in Sierra Valley and actually to meet 

 the ranges of other surrounding forms. It is mainly a Canadian Zone 

 species, but locally extends into the Hudsonian and to a lesser extent 

 down into the Transition Zone. 



Specimens examined. — -Total number, 360, as follows: 

 California: American River (head of South Fork), 2; Aspen Meadows, 2; Big 

 Trees, 3; Bloods, 1; Blue Canyon, 8; Bhie Lake, 3; Buck's Ranch, 2; Burney 

 (12 miles west), 1; Calaveras Big Trees, 3; Carberry Ranch, 8; Cisco (Placer 

 County), 25; Clouds Rest (near, meadow above Little Yosemite), 2; Donner, 

 21; Donner Lake, 3; Echo, 16; Emerald Bay, 24; Fallen Leaf Lake, 9; Gard- 

 ners, 1; Gates Creek, 1; Greenville (8 miles west), 2; Hat Creek (head), 1; 

 Heather Lake (Eldorado County), 1; Hermit Valley, 2; Hope Valley, 7; Inde- 

 pendence Lake, 18; Independence Lake (pass west of), 1; Lassen Peak (north 

 slope), 9; Lincoln Creek (Sierra County), 1; Little Yosemite, 2; Long Valley 

 (Willow Ranch), 1; McCloud (12 miles northeast), 1; McKinneys, 13; Marklee- 

 ville, 11; Mihord, 4; Mill Creek (Mount Lassen), 2; Mokelumne River (head), 

 2; Mono Pass, 3; Mount Conness, 4; Mount Dana, 8; Mount Lyell, 1; Mount 



iNo. 100274, U. S. Nat. Mus., from Camp Agassiz, on Moimt Tallac. 



