462 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.47. 



Adult in summer molt (54070, Whitewater, California, June 8): 

 Much, darker than in any other stage of pelage, and most resembling 

 younger animals in the post-juvenile coat. The general color of the 

 upperparts is greatly darkened by the thinning of the longer overlying 

 hairs and the consequent mixture of the slaty-gray underfur into the 

 coloration. Ear tufts not conspicuous. Juvenile (136227, Oro Grande, 

 California, March 16) : Resembling the young of perpallidus, but still 

 paler, more grayish-drab, the nose and ears with more whitish. Very 

 much paler than the dark young of 0. t. ramona. Post- juvenile pelage 

 (54072, Wliitewater, California, June 9; apparently in second year): 

 Upperparts uniformly silky pale wood-brown, with a wash of cinna- 

 mon on nape and shoulders; ear tufts white, conspicuous. 



STcull. — The skull of OnycJwmys torridus pulcJier does not differ in 

 any special characters from other races. The anterior palatine 

 foramina end about even with plane of fronts of m^; the posterior 

 edge of the palate is rather variable, sometimes slightly concave, 

 usually truncate, often with imperfectly developed spine. 



Measurements. — Averages and extremes of nine adults: Total 

 length, 136;(120-145); tail vertebrae, 48 (37-51); hind foot, 19.6(18.0- 

 20.0); ear from notch in dry skin, 14.5 (12.7-15.5). wSkull: Condylo- 

 basal length, 22.7 (22.0-23.4); zygomatic breadth, 12.7 (12.6-13.2); 

 interorbital breadth, 4.7 (4.4-5.1); breadth of braincase, 11.6 (11.2- 

 11.9); length of nasals, 9.3 (8.8-9.9); length of mandible, 13.2 (12.6- 

 13.7); maxillary tooth row, 3.6 (3.3-3.9). For detailed measure- 

 ments of specimens, see page 481. 



Type-specimen. — No. 12377, Field Museum Natural History, Chi- 

 cago. Skin and skull of female adult (teeth much worn), in late 

 winter pelage. Collected March 1, 1903, by Edmund Heller. 



RemarTcs. — This is a well marked race which differs conspicuously 

 in color from typical examples of all other forms excepting clarus, 

 which it somewhat resembles. It is, however, less intensely bright 

 colored than the Owens Lake form. Specimens from Needles, Cali- 

 fornia, are slightly larger than typical examples of pulcher, thus ap- 

 proaching the dimensions of perpallidus and longicaudus, but they are 

 indistinguishable in color from true pulcher and are still somewhat 

 smaller than the average specimen of perpallidus. A single specimen 

 from Granite Springs, on the north side of the Mohave Desert, is like- 

 wise approaching longicaudus, but clearly belongs best with pulcher. 

 The material from along the Colorado River is rather limited but, as 

 shown by all the specimens examined, the river appears to be a 

 natural barrier between the subspecies pulcher and perpallidus. The 

 animal is rare on the open desert, and is usually found in sandy places 

 along the foothills or borders of streams and washes. Its distribution 

 over the desert is therefore much broken, and large areas of its general 

 range are unrepresented by specimens. The subspecies apparently 



