y o s e m i t e 



NATURK NOTF.S 



Since 1922, the monthly publication of the 

 National Park Service and the Yosemite Natural 

 History Association in Yosemite National Park. 



Vol. XXXV No. 5 



By 



Richard P. Ditton and Donald E. McHenry 



s o C \k^ 



In cooperation with the National Park Service. 



