THE PIPISTRELLE.[186]
The commonest and most generally distributed of the British species is the Pipistrelle,[187] to which the local country name of Flittermouse is considered by Mr. Bell to be specially applicable. In this and the allied species forming the genus Vesperugo, the outer margin of the ear sweeps round on the cheek below the tragus, so as nearly to reach the angle of the mouth, and there is a small membranous lobe outside of the spur which runs from each heel into the interfemoral membrane. There are four incisor teeth in the upper and six in the lower jaw.
PIPISTRELLE IN FLIGHT.
The Pipistrelle is of a reddish-brown colour above, paler beneath. The ears are about two-thirds of the length of the head, somewhat triangular, rounded at the tips, with the upper part of the outer margin deeply concave; the earlet, or tragus, is nearly half as long as the ear, and is of an oblong form with the apex rounded; the wings extend down to the base of the toes, and their membrane, like that of the ears, is of a dusky tint.
This Bat seems to occur abundantly in all parts of the British islands. It is also common on the continent of Europe, as far north as the central parts of Sweden, and southwards to the shores of the Mediterranean, extending thence eastwards through Russia into Siberia and Central Asia, but not passing to the south of the Himalayas. It is essentially an inhabitant of temperate regions. Its favourite resting-places in Britain, according to Mr. Jenyns, are the crevices of decayed brick walls, the cracks of old door-frames, and behind the pipes which are attached to buildings for carrying off rain-water; and Mr. Bell describes it as taking shelter under the roofs of houses, and in crevices of buildings of every description, either inside or out. According to the second edition of Mr. Bell’s work, a specimen has been taken from a hole in the thatch of a low shed in a brick-field, another from a pile of hurdles in a stackyard, whilst a third was observed issuing from the spout of a disused wooden pump, and one was captured from behind a piece of loose bark on a pollard willow near Stratford-on-Avon.[188] The Pipistrelle is thus rather indiscriminate in its choice of a residence, and this may perhaps be due to the fact that its period of winter torpidity is shorter than that of any other species found in the countries which it frequents. In Great Britain it appears on the wing as early as the middle of March, and does not retire for its annual sleep until the winter season has decidedly set in; indeed, Mr. Gould once shot a specimen in the middle of a bright sunny day just before Christmas. Its food consists principally of small insects, especially Gnats, Midges, and other small two-winged flies, but it does not confine itself exclusively to such diet; raw meat possesses such attractions for it that this Bat not unfrequently makes its way into places where this is kept, and may be found clinging to a joint, and making a hearty meal upon it. In confinement, also, the Pipistrelle readily takes small pieces of raw meat as a substitute for its ordinary insect food, and it will become so tame as to take its nourishment from the fingers. On the ground the Pipistrelle runs with considerable ease and quickness, and Mr. Bell states, in opposition to the assertions of certain writers, that it can rise from a flat surface without difficulty. He says:—“We have often seen the Pipistrelle rise from a plane surface with a sort of spring, instantly expand its wings, and take flight. This was repeated by a single individual several times in the course of an hour, and without the slightest appearance of difficulty or effort; it was, on the contrary, evidently a natural and usual action.” The same writer remarks that this Bat climbs with considerable agility, and in connection with this notices a peculiarity in the use of the tail which appears to have escaped other observers, namely, that it is used as an organ of prehension. The last joint of the tail projects a little beyond the interfemoral membrane, and “not only does the animal employ the tail in horizontal progression, in which case it assists in throwing forward the body, by being brought into contact with the ground on either side alternately, corresponding with the action of the hinder foot on the same side; but in ascending and descending a rough perpendicular surface, this little caudal finger holds by any projecting point, and affords an evident support. This is particularly conspicuous when the Bat is traversing the wires of a cage, in which situation the fact was first observed.”
THE NOCTULE.[189]
The Great Bat, or Noctule, is another well-known British species, although far from being so abundant as the preceding. It is, however, even more widely distributed, being found in nearly all parts of the Eastern hemisphere, except the extreme north, but in tropical regions, according to Mr. Dobson, it seems to inhabit only the high grounds. In England it ranges as far north as Yorkshire. Its head and body measure about three inches in length, and its wings are about fourteen inches in expanse. Its fur is of a reddish-brown colour, nearly uniform throughout; the ears are ovate-triangular, shorter than the head, broad, and having the outer margin produced down upon the cheek below the level of the angle of the mouth; the earlet is short, not more than one-third the length of the ear, broad, with the outer margin rounded and the inner one concave. The wing-membranes reach only to the ankle-joint, and there is a distinct lobe outside each of the spurs.
HEAD OF NOCTULE.