U. S. GEOLOGICAL SURVEY OF THE TERRITORIES. MURIDA, PLATE VY. 
Figs. 58-61, Arvicola austerus (1862). Figs. 62-65, A. austerus (945). 
Figs. 66-69, A. curtatus (12196). Figs. 70-73, A. pinetorum (L930). 
Figs. 74-77, Synaptomys cooperi (6915). 
