1 94 Osgood — White-footed Mouse from Crdifoni la. 



with an evident dark median dorsal line, sides brownish fawn, being- of 

 a shade somewhat between the chocolate and fawn color of Ridgway 

 (PL III, figs. 2 and 22): ears lightly edged with whitish, lanuginous tufts 

 usually with a few white or whitish hairs; dark spot at base of whiskers 

 nearly obsolete; underparts white; tail sharply bicolor. 



Skull. — Not definitely distinguishable from that of Peromifscvs oreas;\ 

 decidedly larger and heavier than in P. a u titer us; braincase fuller and 

 wider; rostrum and infraorbital region heavier; audital bulla" larger. 



Measurements. — Although the skull of P. rubidus is not appreciably 

 smaller than that of oreas the hind foot is constantly smaller and the 

 tail shorter. The following table indicates this difference. 



Per amy sens oreas. 



Locality. 



Mt. Baker Range, B. C. 

 Mt. Rainier, Wash 



Average, 6 adults. 



Hind 

 foot. 



24 

 24 

 24 

 23 

 23 

 23 



23.5 



J'eroi// (/.•«■ lift (/rf((s rubidus. 



Locality. 

 Mendocino, Calif 



Briceland, Calif 



Hoopa Valley, Calif. 



Average, 6 adults 



Length. Tail. 



193 



96 



Hind 



foot. 



21.5 



fin the series before me the nasals are very slightly longer in oreas than 

 in rubidus but it does not seem safe to assume that this slight difference 

 is constant. 



^Coll. of E. A. and O. Bangs. 



