1918] Grinnell: A Synopsis of the Bats of California 339 
Genus Corynorhinus H. Allen 
This genus is found only in the warmer portions of North America, 
from southern British Columbia to southern Mexico. Three species 
are now recognized, one of which is divisible into four races. 
Diagnosis—KEars very long, about three-fourths length of fore- 
arm; tragus slender, pointed at tip and wholly free from external 
basal lobe of ear. 
Description: Head—Muazzle slender; greatest width of rostrum 
less than one-third total length of skull. This slenderness, however, 
is somewhat concealed by club-shaped glandular masses which rise 
on each side of snout, between nostril and eye, to a height of 2.5 
millimeters (in an alcoholic specimen) above sur- 
face of rostrum, the two of which converge nearly 
to meet in the median line. Nostrils irregularly 
quadrate and placed on sides of muzzle, opening 
outwards and slightly upwards; borders of nostrils 
slightly thickened, giving them a rimmed appear- 
ance. Ears very large (text-fig. S), being about 
three-fourths length of forearm, and joined across 
forehead by a narrow band of membrane. Tragus 
straight and slender, about two-fifths height of ear. 
Anterior border of auricle strongly convex and 
turned abruptly backward so as to rest upon dorsal Fig. &. Side 
surface of ear almost to its bluntly rounded tip. view of head of 
Posterior half of ear marked by a series of trans- Corynorhinus — raf- 
inesquit pallescens 
verse velnings, most prominent near center of ear 
and fading away towards its posterior border. 
(See pl. 15.) 
(drawn from speci- 
men no. 9368), X 
1.00, showing long 
ear, long acutely 
pointed tragus, 
and glandular 
swelling on side of 
muzzle. 
Skull and Teeth—Skull slender, with com- 
pressed zygomata ; brain-case elongate and rounded, 
in profile shghtly depressed on top and convex 
anteriorly; rostrum coneave in profile, sloping 
abruptly downward from its junction with brain- 
ease. Auditory bullae large and rounded; their greatest diameter 
equal to about three times distance between them. (See pl. 23, fig. 50; 
pl. 24, fig. 58.) 
Mental cf Te Bare lke 2-2 3-3 36. I 
ental formula: 1 == wa o0n nner upper 
3-9’ © 7-7? PM3 9: Ma 5 pp 
incisor about one-third higher than outer, and frequently bicuspidate ; 
in western specimens this character varies greatly. Lower incisors 
about equal in height and slightly crowded in the tooth-row; exceeded 
in height by cingulum of canine. First upper unicuspid (pm?) 
minute, the second (pm*) unusually broad, its greatest width 
equaling its height from cingulum to tip. First and second lower 
unicuspids (pm; and pm;) small, less than two-thirds height of third 
(pm ;) ; all conical and with complete cingula. Cusps of lower molars 
particularly high and sharp. 
Limbs and Membranes——Wing short and broad, length of fifth 
metacarpal equaling that of third; wing membrane attached at side 
of metatarsus, just below bases of toes. Calcar neither keeled nor 
