208 Proceedings of (he Biologlcid Societi/ of Washingto'n. 
latter more distinctly hicolor, dark l)ro\vn above and dnll whitish below; 
ears smaller than in montanus and more hairy. 
Material. Thirteen specimens: 2 (Nos. 11,1)47, 11,1)48) from Independ¬ 
ence hake, 7000 leet altitude, Nevada Comity, taken by A. M. Alexander 
and L. Kello^rg; 7 (Nos. 19,;501)-11),315) from (d.«co, OOOO feet altitude, 
Placer Comity, taken by .1. Crinnell and F. H. Holden; 4 (Nos. 12,975- 
12,978) from 5 o.semite Valley, 4000 feet altitude, iMarijiosa Comity, taken 
liy J. and II. ^V. Crinnell. All the.se localities are in high Transition or 
Canadian Zone, in the cimtral Sierra Nevada of California, and the mice 
Avere trapped in wet meadows. The zonal range of M. m. montanus, of 
northern California, appears not to extend higher than low Transition, 
while that of M. m. datc.heri Bailey, of the high sonthern Sierras in the 
vicinity'of I\ronnt Whitney, extends from Canadian np throngii Hnd- 
sonian. 
Measurements.—id type (old adnlt female): Total length, lOO mm.; 
tail, ol ; hind foot, 20; basilar lengtli of hensel, 24.7; zygomatic width, 
16.2; mastoid width, ]g.2; length of nasals, 7.6; height of hrainca.se at 
hnllae, 9.7. Three old males, one from 'Vosemite and two from Indi‘- 
pendence Lake, measure, respectively: lengths, 185, 175, 177; tail, 46, 
48, 4:>; hind foot, 21, 21, 21. 
Comparisons. —The relatively gray cast of coloration as com]tared with 
M. m. montanus, obtains akso when compared with M. m. dutcheri. The 
latter is mnch more reddish above, and nsnally has a hnffy wash below, 
entirely lacking in the other two forms. In size and hairiness of ears 
[losemite is apparently intermediate between montanus and dutcheri, 
though the differences here involved are slight. In respect to cranium, 
jiosemite as compared with montanus seems to have more widely spread¬ 
ing zygomatic arches and more angular braincase. While there seem to 
be other minor skull differences, there is not available a sufficient series 
to indicate fully the nature and range of individual and age variations. 
