1913] Grinnellr-Swarth: Birds and Mammals of San Jacinto 339 



We have tested the matters of angularity of skull, shape of 

 interparietal, width of interorbital constriction, development of 

 supraorbital bead, and outline of palate posteriorly, and find 

 all these features subject to much variation. Of course age has 

 been taken into account in our examination, as indicated by 

 degree of emergence and wear of the molar teeth. As far as 

 our studies have gone none of the features just mentioned affords 

 a character of tangible worth in distinguishing intermedia from 

 desertorum. The general large size of intermedia covers much 

 of the alleged difference in minor features. 



According to Goldman in his revision (1910, p. 45) N. i. 

 gilva is identical with intermedia in cranial characters ami gen- 

 eral size, differing only in paler, more yellowish, coloration. It 

 is further stated (Goldman, 1910, p. 76) that "in general appear- 

 ance" desertorum "closely" resembles gilva. 



The above preliminary outline of the elements to be con- 

 sidered brings us to the critical treatment of our series of white- 

 footed wood rats from the San Jacinto area. At the outset we 

 are confronted by a baffling lack of uniformity exhibited through- 

 out the material. Characters of .V. i. intermedia, X. i. gilva and 

 N. i. desertorum are varyingly presented. The situation is there- 

 fore best met by dealing with each locality separately. 



Of the two specimens from Garnet Queen Mine, one is young, 

 the other an old adult male. The latter measures small for 

 intermedia; its skull is small with relatively blunt rostrum, like 

 desertorum, but the audital bullae are small as in intermedia. 

 In color both specimens are paler than intermedia and identical 

 with examples from Banning, the type locality of gilva. 



The three specimens from Kenworthy, two old adults and one 

 young one, are in their dark colors throughout good intermedia. 

 But they are, again, rather small : male, 320 x 152 x 33 ; female, 

 295 x 130 x 32. [To appreciate size values, the appended charts, 

 figs. a-c. should be consulted.] Cranially these examples are 

 slightly smaller than average intermedia, but otherwise identical 

 with this form, topotypes of which are at hand from Dulzura. 



The Vallevista series of thirteen are cranially intermedia ; in 

 coloration they are pale like the Banning series, save that one 

 example (no. 2293) is paler still, practically the same shade as 



