Page:Encyclopædia Britannica, Ninth Edition, v. 15.djvu/432

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410 MAMMALIA [CHIEOPTEKA. of very remarkable physiognomy (as may be seen from tig. 70), limited to the Austro-Malayan subregiou. Cephalotes, i , c -J-, pin f, m f> premaxillary bones not united iu front, nostrils simple, muzzle short, index finger without a claw, tail short, includes two species, having the same distribution as those of Ilarpyia ; in both the wing-membrane arises from the centre line of the back, to which it is attached by a longitudinal very thin process of the integument ; the wings are quite naked, but the back covered by them is well clothed with hair. Notoptcris, i f, c , pm f, m f, index finger without a claw, wings from the spine, tail long. With this genus we enter the second division of the family, the Macroglossi, which have the facial part of the skull much produced, the molar teeth narrow, and scarcely raised above the gum, and the tongue exceedingly long, attenuated in the anterior third, and armed with long recurved papilhe near the tip. The single representative of the genus, N. macdonaldii, inhabits the Fiji Islands, Aneiteum Island, and New Guinea. It is at once distinguished from all other Bats of this family by the remarkable length of its tail, which is nearly as long as the forearm. Eonycteris, i -f-, c , pm -|, m f , is also represented by a single species, E. spcl&a, from the Farm Caves, Moulmein, Bunnah, which has somewhat the appearance of a Cynonycteris, but the absence of a claw in the index finger and the presence of the characteristic tongue and teeth at once distinguish it. Macroglossus and Mclonycteris, each with a single species, are closely allied ; the index finger in both has a claw, but the number of the teeth is the same as in Eonyctcris. Macroglossus minimus is the smallest known species of the suborder ; it is much smaller than the common Serotine Bat of Europe, and its forearm is scarcely longer than that of the Long-eared Bat. It is nearly as common in certain parts of India as Cynoptcrus marginatus (compared with which it is proportionally equally destructive to fruit), and extends eastward through the Malay Archipelago as far as New Ireland, where it is associated with Mclonycteris melanops, distinguished from it by its larger size and by the total absence of the tail. SUBORDER II. MICROCHIROPTERA. Insectivorous (rarely frugivorous or sanguivorous) Bats, of com paratively small size, having the crowns of the molar teeth acutely tuberculated, marked by transverse grooves, with the bony palate naiTowing abruptly, not continued backwards laterally behind the last .molar ; with one rudimentary phalanx (rarely two phalanges or none) in the index finger, which is never terminated by a claw ; with the outer and inner sides of the ear-conch commencing interiorly from separate points of origin ; with the tail, when present, contained in the interfemoral membrane, or appearing upon its upper surface ; with a simple stomach (except in Desmodontcs) ; and with the Spigelian lobe of the liver very large, the caudate lobe generally small. Inhabiting the tropical and temperate regions of both hemispheres. The Bats included in this suborder are mainly insectivorous, though some are frugivorous, and two species are known to be sanguivorous. They fall into five natural families, which may be arranged in two groups or alliances as follows : I. Tail contained within the interfemoral membrane ; the middle pair of upper incisors never large, always separated from each other by a more or less wide space. I. Vcspertilioninc Alliance, a. Middle finger with two osseous phalanges only (except in Myxopoda aurita, Tliyroptera tricolor, and Mystacina tuberculata}. a . First phalanx of the middle finger extended (in repose) in a line with the metacarpal bone. a". Nostrils opening in a depression on the upper surface of the muzzle, surrounded by foliaceous cutaneous appendages. a ". Tragus none ; premaxillary bones rudimen tary, represented by thin osseous lamina; suspended from the nasal cartilages in the centre of the space between the canines. RhinolopMdse. b ". Tragus distinct ; premaxillary bones cartila ginous or small, separated by a space in front. Nyctcridse. I". Nostrils opening by simple crescentic or circular apertures at the extremity of the muzzle, not surrounded by distinct foliaceous cutaneous appendages ; premaxillary bones small, lateral, separated by a wide space in front ; tragus distinct. Vespertilionidse. II. Tail perforating the interfemoral membrane, and appearing on its upper sujtface, or produced considerably beyond the truncated membrane ; the middle pair of upper incisors generally large and close together. II. Emballonurine Alliance. U. First phalanx of the middle finger folded (in repose) on the dorsal surface of the metacarpal bone (except in Noctilio and Mystacina}. c". Nostrils opening by simple circular or valvular apertures at the extremity of the muzzle, not surrounded or margined by foliaceous cutaneous appendages; tragus distinct, Emlallonuridse. b. Middle finger with three well developed osseous phalanges ; first phalanx of the middle finger short ; nostrils in the front part of the cutaneous nasal appendages, or opening by simple apertures at the extremity of the muzzle ; chin with warts or erect cutaneous ridges ; premaxillary bones well-developed, united in front. Phyllostomidss. I. VKSPEKTILIONINE ALLIANCE. Family VESPERTILIONID2B. In the above synopsis of the families of Microchiroptcra the Vcspcrtilionidie take the centraj. position; and this is, indeed, the place really occupied by them in the suborder. This family includes the common simple-faced Bats of all countries, of which the well-known Pipistrelle and the Whiskered Bat ( Vespertilio mystacinus) may be taken as familiar types, and its species number about 150, considerably more than one-third the total number of the known species of Chiroptera, estimated at slightly over 400 (see Introd. to Dobson s Catal. Chiropt. Brit. Mas., 1878). Besides the characters of the family giyen in the synopsis, it may be added that the skull is of moderate size, the nasal and frontal bones not much extended laterally or vertically, nor furrowed by deep depressions ; the number of incisors varies from | to -j, rarely (in Antrozous only) ^, premolars - or -| or -J-, rarely (in Vesperugo noctivagans of North America) f ; the upper incisors are small, separated by a wide space in the centre, and placed in pairs or singly near the canines ; the molars are well-developed, with acute W-shaped cusps. The family is distributed over the temperate and tropical regions of both hemispheres. The genera may be con veniently divided into four groups : Plccoti, Vespcrtiliones, Mini- opteri, and Tliyroptcri. In the Plccoti, of which the common Long-eared Bat (Plccotus auritus) is the type, the crown of the head is but slightly raised above the face-line, the upper incisors are close to the canines, and the nostrils are margined behind by grooves on the upper surface of the muzzle, or by rudimentary nose-leaves ; the ears also are. generally very large and united. Of the five genera, Plccotus, i f, pm, f, has two species: one the common Long-eared European Bat referred to abov 3 ; the other, P. rnacrotis, restricted to North America, is distinguished by the great size of the glandular pro minences of the sides of the muzzle, which meet in the centre above and behind the nostrils. Synotus, i f, pm f, distinguished by dentition and by the outer margin of the ear being carried forwards above the mouth and in front of the eye, includes the European Barbastelle Bat, S. barbastdlus, and 8. darjelingensis from the Himalaya. Otonycteris, i %, pm J, connecting this group with the Vespcrtiliones through the tropical Scotophili, is repre sented by a single species, 0. hemprichii, from North Africa and the Himalaya. The next two genera are distinguished by the presence of a rudimentary nose-leaf: Nyctopliilus, i -J-, pm J, with one species, N. timoricnsis, from the Australian region ; and Antrozous, i > pm i, distinguished from all the family besides by having but two lower incisors, and from other Plccoti by the separate ears ; the single species, A. pallidus, inhabits California. The group Vespcrtiliones, with eight genera, includes nine-tenths of the species. Of these one-third are contained in the genus Vesperugo, which is divisible into six subgenera according to the number of premolars and incisors; the latter vary from -| to J in the subgenera Scoto~ous and Rhogcessa, and the premolars from | to (in the subgenus Lasionyctcris f ). The Bats of this genus are generally easily distinguished by their comparatively thickly formed bodies, by their fiat broad heads and obtuse muzzles, by their short, broad, and triangular, obtusely-pointed ears, by their obtuse and usually slightly incurved tragus, by their short legs, and by the presence in most species of a well-developed post-calcaneal lobule. This lobule (which is supported by a cartilaginous process derived from the calcaneum) may act as a kind of adhesive disk in securing the animal s grasp when climbing over smooth surfaces. Vesperugo probably contains the greatest number of individuals among the genera of Chiroptcra, and, with the exception of Vespertilio, its species have also the widest geographical range, being iu fact cosmopolitan ; and one of the species, the well-known Serotine, V. ( Vespcrus) serotimcs, is remarkable as the only species of Bat known to inhabit both the Old and the New World; one, V. borealis, has been found close to the limits of the Arctic Circle, and another, V. magellanicus, inhabits the cold and desolate shores of the Straits of Magellan, doubtless the Bat referred to by Mr Darwin in the Naturalist s Voyage. Clmlinolobus agrees with Vesperugo in the

dental formula, but is readily distinguished by the presence of a