270 UnivcrnHi/ of California Publications in Zoologij. L^'ol. 7 



23752) have the new pehige, and the other one (no. 23744) is still 

 in the i)roce.ss of molt. The new pelage, as shown by this speci- 

 men, is brighter buffy. 



Three of the Nevada animals (nos. 7878, 8313, and 7877) are 

 yonng adults, as is shown by the degree of development of their 

 skulls, their bluer coloration, the character of their pelage, and 

 by their smaller measurements (see table). 



The frontal and parietal regions of the skull are much less 

 inflated in the Nevada specimens than in columhianus, and the 

 incisors average slightly broader. The only comparable skull of 

 levipes is no. 41340, for no. 40641 is evidently a young animal, 

 and its size is not typical. The animals from Quinn River 

 resemble no. 41340, although they are somewhat smaller. The 



Cranial Measurements* op Perodipus microps levipes From Humboldt 



County, Nevada. 



For method of taking measurements, see Introduction. 

 All dimensions are in millimeters. 



Cranl\l Measurements of Young Adults of Perodipus microps Icvip 



« s 



w ; 



w: ^ v. X' a; w 



_ iS c K - "— - 



a K M a<- ai C-r;=.2-5 — 



3 OJ 'V r4 o Q^ o) _cay^^^;ii 



s ' '■'■ y ^ .-St. g So .ic t't:-^ 



7877 ^ 36.9 23.5 19.1 12.3 2.6 2.9 34.9 12.8 

 8313 c? 35.8 22.6 12.1 2.5 3.2 34.0 12.4 



7878 $ 22.1 2.0 12.2 



Avorajfc of the 



young adults 36.3 22.7 19.1 12.2 2.5 3.0 34.4 12.4 



* For s[icfi;il nii'tliods of taking nicMsunMncnts sec the talde on page 26S. 



