corresponding to our middle finger, being always the
longest of all.

Just as is the bird's wing, these various parts can be folded together
or extended by the action of the muscles, but in the Bat the long
fingers become separated when the wing is stretched out, and by this
action they at the same time stretch a thin leathery double membrane
in which they are enclosed, which is thus converted into a broad
surface for striking the air in flight. This membrane is continued
from the fingers to the sides of the body, and even to the hind limbs,
which are often included in it to the ankle-joints; while in the great
majority of Bats there is even a further portion of membrane between
the hind legs, enclosing the whole or a portion of the tail. There is
usually also a narrow strip of the same membrane in front of each arm,
so that the skin of the animal is extended as much as possible, in
order to give it support in its aerial evolution. It is to be noted
that the long second finger extends to the extreme point of the wing
and that the first finger runs close beside it and thus assists in
stiffening that part of the organ. The thumb is left free, and is
furnished with a rather strong hooked claw.

Supported by the action of these great leathery wings, the Bat flies
about almost incessantly during the twilight, and often late into the
night. In full career its flight is swift, though perfectly
noiseless, and it has the power of executing rapid turns and changes
of direction with the greatest facility, as required for the capture
of its prey, which, in the great majority of cases, consists of the
insects of various kinds that in most places fly by night. In pursuit
of these, the Bats flit rapidly about trees, houses, and other
buildings, now and then resting by clinging for a moment to the rough
surfaces of the walls or the trunks and branches of trees. Old country
church-yards, which are usually full of trees, are naturally favorite
haunts of these nocturnal insect-hunters, offering them an excellent
field for the chase of their prey, while at the same time, the church
itself, with its architectural peculiarities, usually affords them a
safe retirement during the day in the dark and secluded corners of its
structure. Hence in the popular mind the Bat has long been associated
with the church-yard, that spot so dreaded that few can pass through
it after nightfall without experiencing certain peculiar feelings, so
that it is no