List of Illustrations 



FACING PAGB 



Beaver Lodges and a Dam 148 



A Pair of Woodchucks by their Burrow (Arctomysmonax) 152 



Woodchuck (Arctomys monax) . . . -,\ 154 



Prairie Dogs (Cynomys ludovicianus) , ,; , , . 156 

 Western Spermophile (Spermophilus), photographed in 



Colorado . . . . . ... . .. . 158 



Say's Spermophile (Spermophilus lateralis) . . . 160 



White-tailed Spermophile (Spermophilus leucurus) . . 162 



Young of Columbia Spermophile (Spermophilus columbianus) 162 



Say's Spermophile in Snow (Spermophilus lateralis) .. 164 

 Young Prairie Dog (Cynomys ludovicianus), about one-third 



grown ......... 164 



Western Chipmunk (Tamias quadrimtatus) . . . 166 



Chipmunk (Tamias striatus) . . . . . 168 



Gray Squirrel (Sciurus carolinensis) ; . 170 



Red Squirrels (Sciurus hudsonicus gymnicus) . . 172 



Young Red Squirrel (Sciurus hudsonicus gymnicus) . 174 



Hoary Marmot (Arctomys Pruinosus) . . . . 174 



Pine Squirrel (Sciurus hudsonicus richardsoni) . . 176 



Flying Squirrel ( Sciuropterus volans) . . . . 178 



Common Mole (Scalops aquaticus) . . . . 188 



Star-nosed Mole (Condylura cristata) . . . . 188 



Marsh Shrew (Sorex palustris) 188 



Four Common Eastern Bats 198 



Sea-lion (Zalophus calif ornianus) ..... 208 



Sea-lion (Zalophus calif ornianus), barking . . . 210 



Walrus Bulls and Cows (Odobenus rosmarus) . . . 212 



Fur Seals (Otoes alascanus) 216 



Harbor Seals (Phoca vitulina) .. . . . . 216 



Otter (Lutra canadensis) . . . . . . . 222 



Skunk (Mephitis putida), crossing a stream . . . 226 



Mink (Putorius -vison) . . . . . . . 234 



Weasel (Putorius noveboracensis) . . . . 234 



American Sable or Pine Marten (Mustela americana). . 244 



Wolverine or Carcajou (Gulo luscus) . . . . 246 



