292 University of California Publications in Zoology [Vou.17 
the angle or ‘‘saddle’’ between the rostrum and brain-case, which 
is shown so clearly in many forms of Myotis. The tooth-row (length 
5.2 to 5.5 millimeters) is much longer in orinomus than in californicus. 
Measurements.—Average and’ extreme measurements in milli- 
meters of a series of ten M. orinomus are as follows: Five males: 
total length, 82.38 (extremes 80.0-86.0); tail vertebrae, 38.4 (37.0— 
40.0); tibia, 12.7 (12.8-13.0); foot, 7.2 (6.0-8.0); forearm, 32.1 
(30.8-33.2) ; greatest length of skull, 13.6 (13.4-14.0). Five females: 
total length, 86.2 (82.0-88.0) ; tail vertebrae, 41.0 (38.0-45.0) ; tibia, 
13.8 (13.5-14.0); foot, 6.5 (6.0-7.0); forearm, 33.7 (32.5-34.6) ; 
greatest length of cranium, 14.3 (13.9-14.7). A comparison of the 
above figures will show that the females average somewhat larger 
than the males. 
Synonymy and History.—The La Grulla brown bat was described 
by Elhot (1903, pp. 228-229) from three specimens obtained in the 
San Pedro Martir Mountains, Lower California, two being taken at 
La Grulla and one at Santa Eulalia. The occurrence of this bat in 
California is first mentioned by Grinnell and Swarth (1912, pp. 
138-141). 
Distribution—Myotis orinomus has been recorded only from 
northern Lower California and from southern California, where its 
range may be defined as the high Upper Sonoran zone, in its semi- 
arid portion, from the east slope of the Sierra Nevada near Owens 
Lake south through the southern Sierras and coast ranges to the 
Mexican line. (See map,-text-fig. O.) 
Specimens Examined.—The writer has examined 17 specimens of 
Myotis orinomus from the following localities in California: San 
Diego County: Dulzura, 3 (Amer. Mus. Nat. Hist., 2; Acad. Nat. Sci. 
Phila., 1); Jacumba, 1 (Amer. Mus. Nat. Hist.) ; Santa Ysabel; 1 
(San Diego Soe. Nat. Hist.) ; Orange County: Trabuco Canon, Santa 
Ana Mountains, 1; Riverside County: Garnet Queen Mine, Santa 
Rosa Mountains, 4; Hemet Lake, San Jacinto Mountains, 1; San Ber- 
nardino County: Doble, 1; Kern County: west slope Walker Pass, 1; 
San Emigdio, 1; Fay Creek, 2; Inyo County: Carroll Creek, on east 
slope Sierra Nevada, 1. 
Natural History.—Nothing has been recorded of the habits of this 
species. 
Myotis evotis (H. Allen) 
Little Big-eared Bat 
Vespertilio evotis H. Allen (1864, pp. 48-50, figs. 42-44). Original 
description; type locality fixed as Monterey, California (see Miller, 
1897b, pp. 77-78). 
Vespertilio evotis, Cooper (1868, p. 5). Distribution. 
