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obscured by black tips of guard hairs; middle and posterior part of back 
blackish, the hairs dull fuscous at base, whitish grey medially, and glossy 
black at tips; rump and base of tail faintly washed with dull ochraceous; 
tail with hairs deep Vandyke brown at base, distal part largely ochraceous- 
tawny, and lightly tipped with brownish black; forelegs light silvery 
grey, running into black on feet; hind legs similar but slightly more dusky; 
under parts uniform dull greyish, the hairs black or dusky at base, some 
with white mesial portion, and some with white and some with black 
tips, the colour of under parts varying slightly on account of wear on 
hair tips; no brownish tint on under parts. Specimens of both adults 
and young are quite uniform in colour. 
External Measurements. Type: total length, 757 ■ 0 (mm.) ; tail 
vertebrae, 212*0; hind foot, 98-0; weight, 25 pounds. Average of three 
adult males (topotypes): total length, 739*0 (757-0-710*0); tail vertebrae, 
209*3 (214*0-202*0); hind foot, 99*6 (102*0-98*0); weight 19*0 (25-0- 
10*0) pounds. Allotype (female): total length, 714*0; tail vertebrae, 
190*0; hind foot, 96*0; weight, 25 pounds. 
Skull. Quite uniform in size and proportions in specimens of same 
age, males and females showing little difference. Skull similar in size to 
that of M. c. oxytona, but narrower and tapering more anteriorly, and 
jugals very much broader. Nasals rather long and constricted posteriorly, 
extending some distance back of ends of premaxillae; posterior ends of 
premaxillse considerably expanded. Skull lighter than in M. c. okanagana, 
proportionately longer and narrower, and with zygoma forming less abrupt 
angle with rostrum. Molars rather large and heavy. 
Skull Measurements. Type (male): condylo-basal length, 101*5; 
palatal length, 51*0; postpalatal length, 43*0; length of nasals, 41*0; 
zygomatic breadth, 64*0; mastoidal breadth, 47*5; least interorbital 
breadth, 25*0; rostral breadth, 23*5; maxillary molar row, 23*5; height 
of skull, 37*0; ratio of zygomatic breadth to condylo-basal length, 63*1. 
Allotype (female): condylo-basal length, 102*0; palatal length, 51*0; post- 
palatal length, 41*0; length of nasals, 44*5; zygomatic breadth, 64*5; 
mastoidal breadth, 47*5; least interorbital breadth, 27*0; rostral breadth, 
24*0; maxillary molar row, 23*0; height of skull, 38*5; ratio of zygomatic 
breadth to condylo-basal length, 63 * 2. 
Comparisons. The Chilcotin hoary marmot differs from all other 
known forms of the caligata group in much greater amount of black in 
the coat, less white on shoulders and anterior part of back, and absence 
of brown on under parts. M. c. oxytona , which ranges to the east and 
north of this form, has much more brownish on upper parts and more 
whitish below. M. c. cascadensis, of the Cascade mountains of south- 
western British Columbia, has more or less brown above and below, 
and colours are more mixed and dingy. M. c. okanagana of the southern 
interior has more brown on the back and under parts are more whitish, 
in some cases shading into brown. M. c. nivaria of the Rocky mountains 
of northwestern Montana, northern Idaho, and southwestern Alberta 
(probably also extreme southeastern British Columbia), is much whiter 
both above and below, and M. vancouverensis is a uniformly brown insular 
