Page:Encyclopædia Britannica, Ninth Edition, v. 15.djvu/436

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414 M A M M A L I A OHIROPTEEA. projecting from its concave surface near the base, also in the sole of the foot and inferior surface of the leg, as shown iu fig. 84. The plantar surface, including the toes, is covered with soft and very lax integument deeply wrinkled, and each toe is marked by a central longitudinal groove with short grooves at right angles to it, of Bats, like Mcgadcrma lyra oi the eastern hemisphere, which it resembles in many respects. The species may be divided into two sections, according as the tail is produced to the hinder margin of the interfemoral membrane or perforates it and appears upon its upper surface. Those included in the first section fall into three genera, Lonchorhina, Macrotus, and Macrophyllum, the first-named including a very remarkable species, L. aurita t with an extraordinary long nose-leaf and peculiarly large ears and tragi. In the second section are included the genera Vampyrus, LopJio- stoma, ScJiizostoma, Trachyops, Phylloderma, Phyllostoma, Tylostoma, Mimon, Carollia, and Ehinophylla, all, with FIG. 84. Thumb and Leg and Foot of Mystacina tulerculata (enlarged). Dobson, Proc. Zoo!. Soc., 187 G. as in the genus Hemidactylus (Geclcolidsc,). The lax wrinkled integu ment is continued along the inferior flattened surface of the ankle and leg. These peculiarities appear to be related to climbing habits in the species. See the writer s remarks in Proc. Zool. Soc., 1876, p. 488. Family PHYLLOSTOJIID.E. The Bats included in this family are readily distinguished by the presence of a well-developed third phalanx in the middle finger, associated either with distinct cutaneous nasal appendages, or with well-developed central upper incisors, or with both. Unlike the Rhinolophidss, their eyes are generally large, and the tragus well developed, maintaining almost the same form throughout the species, however much the outer parts of the body may vary. Their fur is of a dull colour, and the face and back (in the Stenodermata especially) are often marked with white streaks, as in the Pteropodidse, of which they take the place in the western hemisphere. A few species, probably all those with the tail and interfemoral membrane well-developed, feed principally on insects, while the greater number of the species of the groups Vampyri and Glossophagaz appear to live on a mixed diet of insects and fruits, and the Desmodontes, of which two species only are known, are true blood- tropical and sub- suckers, and have their teeth and intestinal tract specially modified in accordance with their habits. Limited to the tropical tropical parts of Central and South America. Subfamily 1. Lobostominse. Nostrils opening by simple apertures at the extremity of the muzzie in front, not margined by a distinct nose-leaf ; chin with expanded leaf- like appendages. It includes two genera. In Chilonyctcris (six species) the crown of the head is moderately elevated above the face-line, and the basi- cranial axis is al most in the same //Cx^y . ^,- ^- /X plane as the facial, ../ /,,. v while in Mormops / >liii fl*-V ^^v> the crown of the / head is greatly ele vated above the face- line, and the basi- cranial axis is almost at right angles to the facial ; i f , pm | in both genera. The latter genus contains two species, which, in their very peculiar physiognomy, are probably the most remarkable among the many strange forms exhibited by the different species of this order. Subfamily 2. Phyllostominse. Nostrils opening on the upper surface of the muzzle, the nasal apertures more or less surrounded or margined by well-developed cutaneous appendages, forming a distinct nose-leaf ; chin with warts. Group I. Vampyri. Muzzle long and narrow in front, the distance between the eyes generally less than, rarely equal to, the distance from the eye to the extremity of the muzzle,; nose-leaf well-developed, horse-shoe-shaped in front, lanceolate behind ; interfemoral membrane well-developed ; tail generally distinct, rarely absent ; inner margin of the lips not fringed ; i f or f, pm f or | ; molars with W-shaped cusps, usually well-developed. Nearly all the species of Vampyri appear to be insectivorous, so that the term applied to this group cannot be considered indicative of their habits. A few, if not all, probably supplement their insect diet with fruit. Vampyrus spectrum (the largest Bat iu the New World, forearm 4 2 inches) is said to be wholly frugivorous, and Macrotus ivaterhousii appears tc prey occasionally on small species FIQ. 85. Head of Mormops lilainviUii. Dobson, Catal. Chiropt. Brit. Mus. FIG. 80. Head of Phyllostoma elonrja- the exception of the last, dis- turn. Proc. Zool. Soc., 1866. tinguished from one another chiefly by the form, of the skull and the presence or absence of the second lower premolarj Trachyops, Phylloderma, and the three last-named genera aro each represented by a single species. Phyllostoma hastatum, fore arm 3 - 2 inches, next in point of size to Vampyrus spectrum, is a well-known species in South America; Ph. clongatum (see fig. 86) differs in its smaller size and much larger nose-leaf. Carollia Irevicauda, a small species, is generally found represented in col lections, and externally so closely resembles Glossophaga soricina (of the next group) that it has often been confounded with that species. It forms a connecting link between this group and the next EMnoyliylla pumilio, forearm 1 25 inches, tail none, is the smallest known species of the family ; it is further distinguished by the narrowness of its molars, which do not form W-shaped cusps, and by the very small size of the last upper molar, characters connecting it, and consequently the group, with the Stenodermata. FIG. 87. Head of Chocrcnyctcris mcxicana, shoving fibrillated tongue. Dobson, Cat. Chiropt. Brit. Mus. Group II. Glossophaga&. J&MXS^Q long and narrow; tongue remarkably long and extensible, much attenuated towards the tip, and beset with very long filiform recurved papilla? ; lower lip with a wide groove above, and in front margined by small warts ; nose- leaf small ; tail short or none ; i f , pm % or f or f , m f or f or  ; teeth very narrow ; molars with narrow W-shaped cusps, sometimes indistinct or absent ; lower incisors very small or deciduous. The ten species included in this group represent seven genera, which are distinguished principally by differences in the form and number of the teeth, and by the presence or absence of the zygomatic arches. The form and position or the upper incisors are extremely variable. In Glossophaga and Phijllonyctcris the upper incisors form, a<j in the Vampyri, a continuous row between the canines ; in Monophylla and Ischnoglossa they are separated into pairs by a narrow interval in front ; while in Lonchoglossa, Glossonycteris, and Chosronycteris they are widely separated and placed in pairs near the canines ; in the first four genera the lower incisors are present (at least up to a certain age), in the last three they are deciduous even in youth. The zygomatic arch is wanting in Phyllonyctcris, Glossonycteris, and Chmronyctcris. The typical species is Glossophaga soricina, which so closely resembles Carollia brcmcauda, both in external form and dentition, that it has frequently been confounded with it. Its long fibrillated tongue (which it possesses in common with other species of the group) led Spix to describe it as a very cruel blood-sucker (sanguisuga crudelissima), believing that it^was used to increase the How of blood. This view is, however, altogether without founda tion, and from the observations of Osburn and others it is evident that the peculiarly shaped tongue is used by the animal, as in the case of the Macroglossi among the frugivorous Ptcropodidse, to lick out the pulpy contents of fruits having hard rinds. The food of the species of this group appears to consist of both fruit and insects, and the long tongue may also be used for extracting the latter from the deep corolla of certain flowers. Group III. Stenodermata. Muzzle very short and generally

broad in front, the distance between the eyes nearly always exceed-