268 



rnirrrsity of California Puhlications in Zoology. [Vol. 7 



Perognathus Flat, Paiiamint ^Mountains, is the type locality 

 of P. m. lei'ipcs. Access to these specimens is through the kind 

 offices of Dr. C. Hart IMerriani. 



Cranial Measurements op Topotypes or Typical Specimens of Ferodipus coJumhi 



AND Perodipus microps levipes. 



For method of taking measurements, see Introduction. 

 All dimensions are in millimeters. 



S< 



31595 

 31147 

 31139 



Locality 



<u 



m 



(S Umatilla, Ore. 

 $ Touchet, Wash. 

 2 Touchet, Wash. 

 Average of typical 

 columbianus 



35.4 

 36.5 

 35.7 



22.2 

 23.2 

 22.1 



CS't- CO 



19.1 

 19.6 

 18.5 



12.8 

 12.9 

 12.8 



•= 5 

 ^^ 



3.1 

 3.1 

 3.0 



"S 5 



2.9 

 3.6 

 3.1 



S^ 



33.6 

 35.1 

 34.2 



12.0 

 12.5 

 12.1 



35.86 22.50 19.06 12.83 3.06 3.20 34.30 12.20 



40641 $ Grapevine Mt?., 



Cal. 34.6 



41340 c? Panamint Mts., 



Cal. 39.0 



Average of typical 



levipes 



36.80 22.60 18.95 12.70 2.45 3.05 35.00 12.35 



* Measured just anterior of external auditory meatus. 

 t Measured at bulge just anterior of posterior end of the bones. 

 t Measured just anterior of point where premaxillaries bend downward. 

 § Measured along median line from most posterior point on supraoceipital to anterior 

 ends of nasals. 



Coloration seems to be unreliable as a diagnostic character. 

 If the near topotypes of these two species were to be mixed with 

 our series it would be impossible to pick them out except by 

 make-up of skins. Size should serve at once to distinejuish 

 columhianus from levipes, for the former has total length, 244.5 

 mm., tail vertebrae, 140.5, and hind foot, 39; while the latter 

 has 289.5, 164, and 42.4, respectively. Adults of our series 

 present the following average measurements: 271.4, l(il.2, and 

 42, respectively. Thus in dimensions the animals from Quinn 

 River Crossing are intermediate between columhianus and 

 levipes, though nearer the latter. 



