69. Feet fully webbed; total length of adult forty to forty-five inches; tail 



long and tapering, and sparsely haired; generally distributed 

 Lutra cayiadensis (Schreber) Otter 

 Feet scarcely or not webbed; less than forty inches long; tail well haired 



70. 



70. Form bear-like; color above dark brown to black, with a band of yellow 



along each side Wolverines 71. 



Form squirrel-like; color not so 72. 



71. Head gri2,2iled gray and brown; along the Canadian border and down the 



Rockies to Colo. 



Gulo luscus (Linn.) Canadian Wolverine 

 Head pale gray above; from the Sierra Nevada Mountains of California 

 northward 



Gulo luteus Elliot Southern Wolverine 

 (Now considered to be a subspecies of the preceding.) 



72. Total length about two feet or over; legs as dark as, or darker than, the 



body color 73. 



Total length less than twenty inches; legs seldom darker than the back — 

 Mustela Linn. (Putorius Cuvier) Weasels (A difficult group to 

 identify by external characters, especially in winter, when many of 

 them turn white.) 77. 



73. With five teeth on each side of the upper jaw behind the canines — Martes 



Pinel (Mustela Linn.) 74. 



With four teeth on each side of the upper jaw behind the canines — ■ 



Mustek Linn. {Putorius Cuvier) 76. 



74. With a dark throat patch; head and shoulders grayish; northern and 



Pacific states 



Martes pennanti (Erxleben) Fisher, Pekan 

 With a light bulf or yellowish patch on the throat; ears often with white 

 or buffy edges 75. 



75. Along the Canadian boundary westward about to Minn., thence north' 



westward 



Martes americana (Turton) Eastern Marten 

 In Washington and Oregon; light areas on throat and chest larger than 

 in the preceding species, often extending on to the front legs 

 Martes caurina (Merriam) Western Marten 



76. Color yellowish-brown, with blackish feet and a black, mask'like band 



across the eyes; plains states 



Mustela nigriceps (Audubon fe? Bachman) Black-footed Ferret 

 Rather uniformly dark brown, except for a white spot on the chin and 

 occasional irregular white spots on the body; generally distributed 

 Mustela vison Schreber Mink 

 (Many intergrading subspecies) 



77. Seldom over eleven inches in total length; tail (not including hair) about 



one-fifth or less total length; no black at the tip of the tail or with only 



a few black hairs (Two common subspecies are given here) 78. 



Often larger; tail more than one-fifth total length; with black at the tip 



of the tail, often for the last quarter 79. 



500 



