NATURAL HISTORY. 
123 
ROOM III.] 
grinders, broad and large wings, with an elongated tail, as long as, and 
inclosed in a large conical interfemoral membrane. The upper cutting 
teeth are near the canines, and separated by a space from those of the 
opposite side. They are divided into genera, according to the form of 
the nostrils and ears. In Nycteris the nostrils are placed in the front 
of a groove ; the grooves are close together in front, and diverge from 
one another behind, and are covered by the spirally indexed outer margin, 
which is notched in front for the entrance of the air. The Petalia of 
Africa only differs from the Nycteris of Asia in the ears being close to¬ 
gether, but not united in front. Nyctophilus , JBarbastellus , and Pie- 
cotus have large united ears like the former, but each of the nostrils is 
seated in the front of a short lunate nasal groove. In Nyctophilus the 
grooves are united behind into an elevated crest, extending across the 
nose; in the other two genera, the grooves are simply lunate, and the 
forehead has an oval bald line, the JBarbastelli having broad sub-quad¬ 
rate, and the Plecoti, elongate ears. The remainder of this tribe of 
Bats have the ears separate on the side of the head. JRomicea has the 
grooves of the nostrils elongated, converging, and united behind into a 
single groove, on the centre of the nose, between the swollen cheeks. 
In the others, each of the nostrils has only a very short groove behind 
it, as the genus Vespertilio , which has thin ears and wings ; and Scoto - 
philus with thick ears and wings. Natalus only differs from Vesper¬ 
tilio in the length of the legs and tail, and especially of the heel bones. 
Pachyotus differs from Scotophilus in the interfemoral membrane being 
slightly, and Lasiurus in its being very hairy. 
The tribe of Bull Dog Bats ( Noctilionina ) have acutely tubercular 
grinders, and feed on insects, like the true Bats, but their wdngs are very 
long and narrow, their bodies thin, and their tails thick ; their lips are 
generally very thick and prominent, resembling in appearance those of 
a bull dog. They are divided into genera according to the position of 
the tail.—In many the tail is short, and the tip is produced on the upper 
surface of the large interfemoral membrane, which is folded inwards 
when the animal is at rest. The genus Mormops is peculiar for having 
a number of differently placed membranaceous ridges on the face and 
chin, giving the animal a most grotesque appearance. Chilonycteris 
has a few T ridges on the chin, and a toothed ridge across the end of the 
nose. These two genera are only found in the West Indies and Cuba. 
The genus Taphozous, only found in Africa and India, has a simple face, 
with a large pit on the forehead; and the males generally have a trans¬ 
verse glandular slit on the throat. The Bull Dog Bat ( Noctilio ) of 
South America, has a very warty muzzle, with large dependent lips; they 
have only two cutting teeth in the lower jaw, which induced Linneeus 
to separate this genus from the rest of the Bats, and to place it with the 
Rats ; the young animals have a wdiite streak on the back. The genus 
Proboscidea differs from the former in the head being long and conical, 
and the muzzle produced and sharp edged, and in having six cutting 
teeth below ; it is found only in Brazil; and Centronycteris only differs 
in the interfemoral membranes being conical and produced. In the 
genus Pteronotus the tail is elongated and produced to the end of the 
conical interfemoral membrane, as in the Vespertilionina ; and the wdngs, 
as in some of the fruit-eating Bats, arise from the centre of the back, 
which is covered with fur on the side beneath them ; their chin is marked 
