Cheieopteea. MAMMALIA. Cheieopteea. xxvii 
from St. Louis, Dr. Allen remarks, has the wing 
membrane attached to the ankles, the foot being en- 
tirely free. In other respects, it agrees with V. luci- 
fugus. This present species is common throughout 
the United States and south to Panama. Its ex- 
panse of wing is 8.6 to 10 inches. 
THE GILA BAT (^Vespertilio yumanensis, Allen ). — 
From that dreaded military post, where the heat is said 
to be “ unutterable,” Major Geo. H. Thomas sent a 
specimen of this Bat, which Dr. Allen has named for 
the locality — Fort Yuma being situated on the Gila 
River. In general appearance, says Dr. Allen, this 
Bat resembles both V. subulatus and Scotophilus 
georgianus. It is, however, smaller than the former, 
the membranes more delicate, the foot proportion- 
ately larger, the interfemoral membrane smaller, but 
it agrees with it in the subulate tragus and in the 
dentition. Its relation to S. georgianus is seen in 
the light brownish snout and ear ; its variance there- 
from, in the longer and more acuminate tragus, the 
smaller size of the thumb, and the difference in the num- 
ber of the molars. Its expanse is from 8.6 to 9 inches. 
THE CALIFORNIA BAT ( Vespertillo nitidus, Allen). 
This is described and named by Dr. Allen, in the 
Proc. Phil. Acad. Nat. Sciences, for 1862. It bears 
a strong resemblance to V. mystacinus of Europe. A 
specimen, labelled V. oregonensis by Dr. Leconte, in 
the Smithsonian Institution, is thought by Dr. Allen 
to be this species. The V. Nitidus is small in body ; 
tlie head and face are very hairy ; the nostrils separa- 
ted by a narrow, slightly emarginate space. The ears 
are longer than the head. The lips are extensively 
whiskered ; the thumb and foot small. The tip of the 
tail is rarely free. The fur is long and silky. 'J'he base 
of the hair is plumbeous, that behind having russet and 
brown tips, and in front it is a lighter russet or ashy 
on the tips. The interfemoral membrane is naked, 
excepting the usual tuft at the shoulders, and a few 
lightish hail’s arranged transversely in front. The 
dentition as in V. evotis. As far as ascertained, 
this species is confined to the west of the Rocky 
Mountains. Its expanse of wing ranges from 7 to 
8.6 inches. 
SvNOTus. — Keyserling and Blasius. 
This genus has, as characters, very large ears, the 
outer border extended anteriorly as far as the tragus. 
There are large excrescences on the nose, continuous 
with the inner border of the ear. A semicircular fold 
is seen on the base of the outer border of the ear. 
It has no tongue-shaped appendage at the base of 
the inner border, as in the genus Plecotus. 
As represented by Keyserling and Blasius in Wiegm. 
Archiv. far Naturg., 1839, this genus includes both 
the species in the United States. It is closely allied to 
Plecotus, a European genus, as both are to Vespertilio. 
'I’he skull is rather large ; cranium is inflated, and it 
has no occipital crest. Dentition is : Molars, f ; 
Canines,!; Incisors,^; Canines,!; Molars, f ; = 
teeth 36. 
THE BIG-EARED BAT {Synotus macrotis, Allen). 
This is the Plecotus macrotis of Leconte, P. lecontii 
of Cooper, Synotus lecontii of Wagner. The head is 
flat, not very broad, and the face is somewhat covered 
with hair. Lips are thin and compressed. 'I’he facial 
crest is elevated on a line with the nostrils, the latter 
being small and membraneous on the edges, and ex- 
ternally wider than internally, opening almost later- 
ally, and with a shallow concavity between them. 
'I'he ears are very large and slightly hairy on the in- 
ternal border. 'I’he tragus is half as high as the ear, 
straight on the inner edge, diverging on the outer, 
and having a circular lobe at the base, almost at right 
angles to the tragus proper. The hair is long, fine 
and soft. On the upper parts it is dark at the base, 
quite blackish ; the tips are dusky and brownish. 
'J'he base of the ear is covered with hair, a delicate 
line extending up the internal border, 'i’he fur of the 
belly is like that of the back. 'I’he interfemoral 
membranes are naked, and tlie base of the thumb, 
also, hairless. The thumb and foot are slender, a few 
long hairs on the back of the latter. 'J’his Bat is 
confined to the South Atlantic States. Specimens 
range from nine to eleven inches in expanse of wing. 
TOWNSEND’S SYNOTUS {Synotus townsendi, Wag- 
ner) resembles the preceding, but is stouter, 
and the membranes are somewhat lighter, 'fhe face 
is broader and more lengthened. 'Fhe crests are high 
and well-defined, with the wart between the internal 
border of the ear and mouth larger than in S. macro- 
tis. The tragus is of the same general shape, with 
marked lobe at the base. 'I’he small ovate lobe near 
the angle of the mouth is seen as in the preceding 
species. 'I’he limbs are slender, aud the thumb and 
foot rather small. 'I’he hair is everywhere thick, fine 
and long. In color it is brown above, the hairs not so 
marked in two colors, the base being only slightly 
darker. In front it is lighter, where it inclines to a 
ferruginous brown at base. 'I’he back of the foot is 
slightly furred. 'I’he dentition is the same as in the 
preceding ; the central incisors of the upper jaw are, 
however, more distinctly bifid at the cutting edge. 
It inhabits the central regions of the United States. 
Specimens are from Utah and Upper Missouri. Tlie 
wing expanse is from ten to eleven inches. It is the 
Plecotus townsendi of Cooper. 
Antrozous. — A lien. 
This genus is established in a paper by Dr. Allen, 
published in Proc. Phil. Acad. Nat. Sci., 1862. It 
differs from Yespertilio in tlie high and slender snout, 
the crested and narrow skull, elevated, broad ears, 
and in having one incisor less on each side, in either 
jaw. 'i’he head is large ; nose high, tapering and 
narrow; the snout angular and blunt; the nostrils 
situated on the apex of the snout ; the outer borders 
are joined above in a transverse line; the eyes are 
large ; the ears are longer than the head, and not 
joined. 'The skull is long, with a small crest at the 
posterior, tapering towards the anterior. The denti- 
tion is: Molars, !; Canines, ! ; Incisors, f ; Canines, 
! ; Molars, ! ; = teeth 28. 
THE PALE BAT {Antrozous pallidus, Allen ). — 
Leconte records it in Proc. Phil. Acad. N S., 1855, as 
Vespertilio pallidus, and Baird, also, the same, in Pe- 
port Mex. Bound. Survey, 1858. The head of this spe- 
