Smithsonian Report. 1941.- Walker 



1. A choice specimen of American mink running a ferris-type wheel in its glass- fronted cage. A small 

 stump and limb on which the animal can climb is behind the wheel. 



1 u(. luL'-i-ared cliff mice running on an inclined disk wheel while a third beneath the wheel watches the 



photographer. 



All photographs taken by the author unless otherwi.se indicated. 



