Page:Encyclopædia Britannica, Ninth Edition, v. 15.djvu/434

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412 MAMMALIA [c HIROrTERA. Megaderma, i |, pm |- or , with five species, is distinguished by the absence of upper incisors, by the cylindrical narrow muzzle sur mounted by an erect naked cutaneous process (the nose-leaf), the base of which conceals the nasal orifices, by the immense connate ears with large bifid tragi, and by the great extent of the interfemoral membrane, in the base of which the very short tail is concealed. M. gigas, from central Queensland (forearm 4 2 inches), is not only the largest species of the genus but also of the suborder. M. lyra, common in India (forearm 27 inches), has been caught in the act of sucking the blood, while flying, from a small species of Vcs- pcrugo, which it afterwards devoured (see Dobson s Monograph of Hie Asiatic Chiroptcra, p 77) ; so that it is probable that the Bats of this genus do not confine themselves to insect prey alone, but also feed, when they can, upon the smaller species of Bats and other small mammals. Nyctcris, i f, pm |, with seven species, differs so much from Megaderma that it may be considered the type of a separate sub family. As in that genus, the frontal bones are deeply hollowed out and expanded laterally, the muzzle presents a similar cylindrical form, and the lower jaw also projects, but the single elevated nose- leaf is absent, and instead of it the face is marked by a deep longi tudinal sharp-edged groove extending from the nostrils (which are on the upper surface of the muzzle near its extremity) to the low band connecting the bases of the large ears ; the sides of this depression are margined as fir back as the eyes by small horizontal cutaneous appendages. All the species resemble one another closely, and are mainly distinguished by the form of the tragus, and the size and relative position of the second lower premolar. "With the exception of N. javanica, all the species are limited to the Ethiopian region. Family EHINOLOPIIID^;. In all the species of this family the nasal appendages are highly developed, and surround on all sides the nasal apertures, which are situated in a depression on the upper surface of the muzzle ; the ears are large and generally separate, without trace of a tragus ; the premaxillary bones are rudimentary, are suspended from the nasal cartilages, and support a pair of very small incisors ; the molars have acute W-shaped cusps ; the skull is large, and the nasal bones which support the large nasal cutaneous appendages are much expanded vertically and laterally ; in females a pair of teat- like appendages are found in front of the pubis ; and the tail is long and produced to the posterior margin of the interfemoral membrane. The family is found in the temperate and tropical parts of the eastern hemisphere. From whatever point of view the Rhinolophidsz may be considered, 1hey are evidently the most highly organized of insectivorous Bats. In them the osseous and cutaneous systems reach the most perfect development. Compared with theirs the bones of the extremities and the volar membranes of other Bats appear coarsely formed, and even their teeth seem less perfectly fitted to crush the hard bodies of insects. The very complicated nasal appendages, which evidently act as delicate organs of special perception (vide supra), here reach their highest development, and the differences in their form afford valuable characters in the discrimination of the species, which resemble one another very closely in dentition and in the colour of the fur. Subfamily I. Rliinolopliinee. First toe with two, other toes with three phalanges each ; ilio-pectineal spine not connected by bone with the antero-inferior surface of the ilium. Rhinolophus, i , c , pm f, m f, nose-leaf with a central process behind and between the nasal orifices, posterior extremity lanceolate, antitragus large, includes twenty-four species. R.luctus, forearm 3 inches, is the largest species, in habiting elevated hill tracts in India and Malayana ; R. hipposideros of Europe, extending into south England and Ireland, forearm 1 5 inches, is one of the smallest; and R.ferrum-cquinum, forearm 2 3 inches, represents the average size of the rpecies, which are mainly distinguished from one another by the form of the nose-leaf. The 1 list-named species extends from Eng land to Japan, and southward to the Cape of Good Hope. Subfamily II. Phyllorhininee. Toes equal, of two phalanges each ; ilio-pectineal spine united by a bony isthmus with a process derived from the antero-inferior surface of the ilium. Fhyllorhina, ii twenty-two species, and Rhinonycteris, Tri&nops, and Ccelops, with one each, represent this subfamily. Pkyllorhina, i 4> c f> P m or i> m T> differs from Rhinolophus in the form of the nose-leaf, which is not lanceolate behind (see fig. 76), and is unprovided with a central process covering the nostrils ; the largest species, Ph. armigcra, appears to be the most northerly, FIG. 76. Head of Khino^ophus mitratus. Bobson, AI:inogr. Asiat. Chiropt. having been taken at Amoy in China, and in the Himalaya at an elevation of 5500 feet. Many are provided with a peculiar froutnl sac behind the nose-lenf, rudimentary in females (see fig. 67), which the animal can evert at plea sure ; the sides of this sac secrete a waxy substance, and its extremity sup ports a pencil of straight hairs. Rhinonycteris, re- FIG. 77. Head of Fhyllorhina ca rarata. Uobson, J roc. Zoo!. Soc., 1877. presented by I. aurantia from Australia, and Triienojis, by T. persicus, from Persia and eastfrn Africa, are closely allied genera ; the latter species is characterized by the very remarkable form of its nasal appendages and ears, and by the presence of a peculiar osseous projection from the proxi mal extremity of the second phalanx of the fourth finger. Cwlops (C. frithii), from the Ben gal Sunderbunds, Java, and Siam (in the roof of the great pagoda at Laos), is distinguished, not only by the very peculiar form of its nose-leaf, but also by the great length of the metacarpal bone of the index finger, as well as by the shortness of the calcanea and inter femoral membrane. FIG. 78. Head of Trixnops persicuf. x 2. Uobson, Alonogr. Asiat. Chiropt. II. EMBALLONUEINE ALLIANCE. Family EMBALLONURID.E. The second group of families (as defined above) into which tho Microchiroptera may be divided includes the Emballonuridx and Phyllostomidee. The former is represented by thirteen genera, including sixty-five species. The Emballonuridse are generally easily distinguished by the peculiar form of the muzzle, which is obliquely truncated, the nostrils projecting more or less in front beyond the lower lip, by the first phalanx of the middle finger being folded in repose forwards on the upper surface of the metacarpal bone, by the tail, which either perforates the inter femoral membrane or is produced far beyond it, and by the upper incisors, which are generally a single pair separated from the canines and also in front. They are cosmopolitan like the Vespcr- lilionidx, but rarely extend north or south of the thirtieth parallel of latitude. Subfamily I. Emballonurinse. Tail slender, perforating the interfemoral membrane, and appearing upon its upper surface, or terminating in it ; legs long, fibulae very slender ; upper incisors weak. Group I. Furise. Tail terminating in the interfemoral mem brane ; crown of the head greatly elevated above the face-line ; thumb and first phalanx of the middle finger very short ; i H{, c , pm -- , m f . Two genera, Furia and Amorphochihis, each including one species of very peculiar aspect, the latter distinguished from the former by the widely separated nostrils and great extension back wards of the bony palate. Habitat South America. Group II. Emballonurse. Part of the tail included in the basal half of the interfemoral membrane, the remaining part passing through and appearing upon its upper surface ; crown of the head slightly elevated ; thumb and first phalanx of the middle finger moderately long; pm%, With five genera. Emballonura, i f, extremity cf the muzzle more or less produced beyond the lower lip, forehead flat, contains five species, inhabiting islands from Mada gascar through the Malay Archipelago to the Navigators Islands. Colciira, i -J-, FIG. 79. Ear of extremity of the muzzle broad, forehead rq/rayana. concave, has two species from east Africa and the Seychelles Islands. Rhynchonyctcris is distinguished from Colciira by the much produced extremity of the muzzle ; the single species, R. naso, from Central and South America, is very common in the vicinity of streams throughout the tropical parts of these countries. It is usually found during the day resting on the vertical x 2. Dobson,

froc. Zocl. Soc., 1873.