HEAD OF BLAINVILLE’S BAT.
(After Peters.)
A most grotesque species of Bat, the position of which has been a subject of some discussion, as it seems to be almost equally related to the Emballonuridæ on the one hand, and to the Phyllostomidæ on the other, was described many years ago (in 1821) by the late Dr. Leach under the name of Mormops Blainvillii. As regards the development of the cutaneous system about the face, this species is without exception the most extraordinary species of the whole order (see [figure]). The skull itself is of curious structure, the cranial portion, or that containing the brain, being so much elevated, that its height is nearly equal to the whole length of the skull, and its front wall descends in such a manner as to form nearly a right angle with the bones of the face (see [figure]). The superficial structures belonging to the face and head are so complicated as almost to defy description, and so grotesque that one might recommend their study to the inventors of demon-masks for pantomimic purposes. The ears are of considerable size, and have their margins notched in several places; they sweep round on the cheek, to terminate at a short distance from the angle of the mouth, and have their inner margins joined by a fold of membrane. The tragus is a thick, more or less lobulated organ. The nostrils are round apertures in the extremity of the snout, their margins are raised and naked, and produced above into small lobes. Between the nostrils there is a perpendicular ridge, and above this a small round papilla on each side of which there is an irregular kidney-shaped elevation. Behind these parts comes a large fold of skin, deeply notched in the middle above, which joins on each side with the middle of the membrane uniting the ears, and probably represents the hinder nose-leaf in some other Bats. The lower lip consists of two leaves, the upper of which forms in the chin a large shield-shaped, warty plate, beneath which the lower leaf and the skin of the throat form a complicated series of lobes.
SKULL (Natural Size) AND DENTITION
(Enlarged) OF BLAINVILLE’S BAT.
The teeth in this Bat consist of four incisors and a pair of strong canines in each jaw, two pre-molars in the upper and three in the lower jaw, and three molars, with more or less distinct W-shaped cusps on each side in both jaws (dental formula—incisors, 44 canines, 1–11–1, pre-molars, 2–33–3, molars, 3–33–3 ). The wings are well developed, long, and broad, and the membranes descend to the ankles (see [figure]); the first phalanx of the middle finger is very short. The interfemoral membrane is ample, and stretched by two very long heel-spurs; it is perforated before the middle for the passage of the tail, about one-third of which projects on the upper surface of the membrane.
The length of the head and body in this species is about two inches and two-thirds, and that of the tail from one inch to one inch and one-sixth, according to the sex, being longer in the male. The fur of the upper side is of a rich umber-brown, and that of the lower surface brownish-grey, the difference being caused by the brown tips of the hairs above, which are wanting on those of the under side. The hairs on the inner margin of the ear are shiny brown. The membranes are dark-brown. This species is an inhabitant of South America and of the West Indies, but it does not seem to be very abundant. Nothing has been recorded as to its habits, but it is probably a strictly nocturnal Bat.
BLAINVILLE’S BAT. (After Peters.)
Blainville’s Bat is the type of a small group of Phyllostomidæ, which, as already indicated, form a sort of transition towards the more normal Emballonuridæ, the line of relationship probably passing through the Noctiliones. This group (Mormopes, Peters; Lobostominæ, Dobson) is characterised by its terminal nostrils, and the cutaneous folds or ridges on the chin.