may be regarded
as exceedingly-modified Insectivora
, having their nearest
ally in Galeopithecus.
They possess one or two pair of pectoral teats; and the
fore-limbs are very long, some of the digits particularly being
immensely elongated. There is a patagium
, or expansion of
the integument, uniting the fore-limbs with the body, and extended,
as a membranous web, between the elongated fingers.
Of these, the third, fourth and fifth, and very frequently the
second, are devoid of nails. The pollex always has a clawlike
nail. When the animal is resting upon the ground, the
thigh is twisted upward and backward, in such a manner that
its extensor face looks forward, and its flexor face backward.
In consequence of this the knee looks upward and backward,
and the toes are turned backward and slightly outward. Under
the same circumstances, all the digits of the manus are
flexed upon their metacarpal bones; and the folded-up wing
rests against the side of the body, while the pollex, with its
claw, is extended forward. In this position the animal shuffles
along, with considerable rapidity; hauling itself forward by
the claws on the polHces, and shoving itself along, by extending
The favorite attitude of a Bat, when at rest, however, is
that of suspension by the claws of one or both legs, with the
head downward and the patagium
folded over it like a cloak,
The most active movement of the Bat is effected by flight, the
fore-limbs being extended, and the patagium,
which they support,
playing the part of the feathers of a bird's wing.
The cervical vertebrae are remarkably large in proportion
to the others, but, as in the rest of the vertebral column, the
spinous processes are very short. The ribs are long and
curved, so as to include a relatively capacious chest. The
manubrium of the sternum is very wide, and the middle of its
under surface raised into a crest. In the lumbar region, the
vertebral column is bent, so as to be concave forward and to
describe almost the quarter of a circle. As a consequence, the
axis of the sacrum is at right angles to that of the anterior
In the skull, the orbit is not divided by bone from the
temporal fossa, and the premaxillae are relatively small, and
sometimes altogether rudimentary.
The clavicles are remarkably long and strong, and the
broad scapula has a strong spine. The ulnae are imperfect
distally, the carpus being borne altogether by the radius.
There is only a single bone in the proximal row of the carpus,
the pisiform being absent. Those digits of the manus which
are devoid of nails possess not more than two phalanges.
The pelvis is very narrow and elongated, and the pubic
bones are widely separated at the symphysis, as in some Insectivora
The anterior caudal vertebrae and the ischia are
frequently united. The axes of the acetabula are directed
toward the dorsal side of the body as well as outward;
whence, in part, arises the peculiar position of the thigh,
which has already been described. The fibula is rudimentary,
its upper part being represented only by ligament, and there
is an elongated bone, or cartilage, attached to the inner side
of the ankle-joint which lies in and supports the patagium
and is called the calcar
. The distal moiety of the tarsus
readily rotates upon the astragalus and calcaneum, permitting
the sole to turn inward with much ease.
possess three kinds of teeth, incisors,
canines, and molars; and the intestine is devoid of a caecum.
The heart is provided with two superior cavae, a right and
left; and the smooth cerebral hemispheres leave the cerebellum
The testes are abdominal throughout life, or may descend
into the perinaeum, but there is no true scrotum. The penis
is pendent. There are vesiculce seminales. The form of the
uterus varies, being sometimes rounded and sometimes two horned.
The Bats are ordinarily divided into the Frugivora
the Insectivora. a.
live, as their name implies, exclusively
upon fruits. With the single exception of Hypoderma
the genera embraced in this group have a nail on the second
digit of the manus, and the crowns of the molar teeth, which
soon wear down, are, when entire, divided by a longitudinal
The incisors do not exceed 2.2/2.2.
The pyloric portion of the stomach is immensely elongated.
The nose has no foliaceous appendages, and the welldeveloped
pinna of the ear has the ordinary form, neither the
tragus, nor any other part, being unusually developed.
These Bats are confined to the hotter parts of the Old
World and of Australia, where, from their dog-like heads and
reddish color, they are known as "Flying-Foxes" (Pteropus,
The division of the Insectivora
contains Bats which, for
the most part, live upon insects, though some delight in fruits,
and others suck the blood of larger animals.
The second digit of the manus is devoid of a nail, and
sometimes is without any bony phalanges.
The stomach is usually pyriform, with a moderate cardiac
enlargement. The molar teeth almost always have such a
pattern as is observed in the typical Insectivora
, and do
not exceed six, or fall below four, on each side above and
The incisors are ordinarily 2.2/2.2 or 2.2/3.3, but their number may be
The integument of the nose is developed into an appendage
which is sometimes very large and leaf-like, and the tragus
of the large ears is often similarly modified. The tail is often
long, and sometimes prehensile.
The genera Desmodus
(of which the group Hematophilina
has been formed) are the most completely
blood-sucking of all the Bats in their habits. They have a
pair of enormous, sharp-pointed, upper incisors, while the four
lower incisors are small and pectinated. The canines are very
large and sharp, and the molars, which are reduced to two
above and three below, on each side, have their crowns converted
into sharp longitudinally disposed ridges, like the;
edges of scissors. In Desmodus
, the very narrow oesophagus
leads into a stomach which would be of extremely small dimensions,
were it not that its cardiac end is dilated into a
great sac, which is longer than the body, and lies, folded up
on itself, within the cavity of the abdomen. Into this sac it
would appear that the blood swallowed by the animal at first
passes, to be thence slowly drawn along the intestine.
Mr. Darwin ("Voyage of the Beagle," Mammalia, p. 2.) thus speaks of the habits Desmodus D' Orbignyi;
"The Vampire Bat is often the cause of much trouble by
biting the horses on their withers. The injury is generally
not so much owing to the loss of blood as to the inflammation
which the pressure of the saddle afterward produces. The
whole circumstance has lately been doubted in England. I
was therefore fortunate in being present when one was actually
caught on a horse's back. We were bivouacking late
one evening near Coquimbo, in Chili, when my servant, noticing
that the horses were very restless, went to see what was
the matter, and, fancying he could distinguish sometliing, suddenly
put his hand on the beast's withers and secured the
Vampire. In the morning the spot where the bite had been
inflicted was easily distinguished, from being slightly swollen
and bloody. The third day afterward we rode the horse without
any ill effects."