344 TJnivt rsity of California Publications in Zoology I Vol. 10 



accrue from the smallness of the series involved, rather than to 

 be of any deeper significance. 



From Snow Creek, up in the foothills three miles southwest 

 of Whitewater, there are thirteen specimens, including adults 

 and young. These are distinctly paler than the average of the 

 Cabezon and Banning series. All, in fact, are to be matched 

 from desertorum in seasonally comparable pelage. In amount 

 of black dorsally and white vent rally, linl of yellowish brown 

 laterally, and dorsal color of tail, we are unable tit distinguish 

 them from desertorum. Also is this true in quality of pelage, 

 though the series is iii worn breeding stage, and hence not so 

 soft as desertorum is in fresh fall pelage. In size some Snow 

 ('reek examples are well toward the upper limit of the range 

 of variation in intermedia: the series averages large. Cranially 

 old adult males are still large, like the ones from Cabezon and 

 Banning, though not so large and long-snouted as intermedia 

 proper. The audita] bullae remain small, but with evident varia- 

 tion. 



Prom Whitewater slat ion. on the floor of the desert sloping 

 up towai'd San Gorgonio Pass, and only three miles Prom the 

 station at Snow ('reek, there are nine, mostly young. These all 

 show the small size, pale coloration, and soft pelage of typical 

 desertorum. [See charts showing variation in measurements, 

 figs, a c. which take account only of adults, j Cranially we 

 can see no difference from desertorum, except in audita! bullae. 

 which are appreciably smaller. This difference, however, van- 

 ishes when selected examples of desertorum are lined up with 

 the Whitewater crania in proper sequence; in other words, while 

 there is average difference in this respect, individual variation 

 mi]' the results of interbreeding) bring an overlapping or inter 

 gradation. From intermedia and gilva from Banning, the White- 

 water crania are markedly distinguished by lesser bulk and 

 shortness of rostra and nasals. 



Unfortunately we have from Palm Springs, well out on the 

 floor of the desert, hut one example. This in all respects, includ- 

 ing audita] bullae, is quite typical of desertorum. It is note- 

 worthy that an obvious intergrade between desertorum and inter- 

 media has been described from Palm Springs. This is "Neotoma 



