262 University of California Publications in Zoology [Vou.17 
Color—tThe six specimens of the Hollister bat which are at hand 
are quite uniform in coloration. Bases of hairs everywhere chaetura 
black, except on anterior portion of throat where they are uniform 
cinnamon buff. Distal portions of hairs on dorsal surface of body 
light sayal brown, with a silky sheen. This shade of brown extends 
down onto sides of belly, which are otherwise pale cinnamon buff, 
varying slightly in exact shade among the different specimens. Mem- 
branes clove brown. 
Skull—asily distinguished from that of any other species of 
Myotis inhabiting California, by its very broad and relatively flat- 
topped rostrum and brain-case (pl. 21, fig. 30; pl. 22, fig. 42). Sag- 
gital crest more clearly defined than in any other Californian Myotis, 
except M. velifer. Teeth essentially as described for the genus, save 
that in four of the eight known SUES HLEDE the upper middle premolar 
(pm2) is missing on both sides. 
Measurements —T he average and extreme measurements in milli- 
meters of the six examples of the Hollister bat in the Museum of 
Vertebrate Zoology are as follows: total length, 87.3 (85.0-90.0) ; tail 
vertebrae, 35.6 (34.0-38.0) ; tibia, 13.9 (13.7-14.0) ; foot, 8.7 (8.0- 
9.0); forearm, 35.6 (35.1-36.4); greatest length of cranium, 15.1 
(14.8-15.4). 
MEASUREMENTS IN MILLIMETERS OF Stx EXAMPLES OF MYOTIS ocCULTUS 
HOLLISTER, FROM IMPERIAL COUNTY, CALIFORNIA 
E - “2 ae 
= ee og SF 
= 3 = a 3s E=iin4 Lan; 
ae 2 = 2 He <5 Su 
Mus. fe 5 Es = i z S SE ee $8 
no. Sex mien cue = oF & te Si [a2] fap 
10702 @ 85.0 35.0 14.0 9.0 35.4 15.2 9.8 7.7 3.9 
10703" @ 89.0 34.0 13.8 8.9 3:01 eee 9.7 -_ 4.1 
10704" 90.0 36.0 14.2 9.0 36.4 15.4 10.1 7.9 4.0 
10705°  Q 86.0 34.0 13.9 8.5 35.2 14.8 9.6 7.3 4.1 
10706 87.0 37.0 13:7, 8.0 36.3 15.3 9.6 7.6 4.0 
107077 @ 87.0 38.0 14.0 9.0 35.1 15.0 9.8 ath 4.0 
1From four miles south of Potholes. 
? From five miles northeast of Yuma. 
Synonymy and History—The Hollister bat was deseribed by 
Hollister (1909, p. 48) under the name JJyotis occultus, from two 
specimens obtained on the west side of the Colorado River, ten miles 
above Needles, San Bernardino County, California, May 14, 1905. 
Distribution—Known only from the west side of the Colorado 
River from near Needles (as above) to near Yuma, where six speci- 
mens were obtained in May, 1910 (see J. Grinnell, 1914, p. 263). (See 
map, text-fig. O.) 
Specimens Examined.—tThe writer has examined eight specimens 
of the Hollister bat, from the following localities in California: Im- 
perial County: five miles northeast of Yuma, 5; four miles south of 
