Page:Encyclopædia Britannica, Ninth Edition, v. 14.djvu/461

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LEMUR milk dentition there are twenty-two teeth, the true molars of course not being represented, but there are two additional teeth in the fore part of the lower jaw which have no successors in the permanent series. Hind limbs greatly developed, but the tarsus normal. Kallux of large size, and very opposable. The other toes united at their base by a fold of skin, which extends as far as the end of the first phalanx. Mamma two, pectoral. Cuecum very large, and colon extremely long and spirally coiled. The animals of this group are, as their organization indicates, essentially arboreal, and feed exclusively on fruit, leaves, buds, and flowers. When they descend to the ground, which is but seldom, they sit upright on their hind legs, and move from one clump of trees to another by a series of short jumps, holding their arms above them in the air. They are restricted geographically to the island of Madagascar. Among them are the largest members of the order. A very detailed and beautifully illustrated account of their charac ters, external and internal, and distribution and habits, is given in the Histoire Naturelle de Madagascar, by A. Grandidier and Alphonse Milne-Edwards (1875). The species are not numerous and are distributed into three genera. 1. Indris, Geoff. Upper incisors subequal in size. Upper canine larger than the first premolar, muzzle moderately long, ears exserted. Carpus without an os centrale. Tail rudimentary. Vertebrae : 07, D12, L9, S4, 09. The only well-established species is the indris (I. brevicaudatiis, Geoff., fig. 1), discovered by Sonnerat in 1780. It is the largest of FIG. 1. Indris (Indris brevicaudatus). From Milne-Edwards and Grandidier, Mammiferes de Madagascar, pi. 12. the lemurs, the length of the head and body being about 2 feet, and the tail 2 inches. It is very variable in colour, for although usually nearly black, marked with whitish spots principally in the lumbar region and fore arm, individuals have been found quite white. It inhabits exclusively the forests of a part of the east coast of Mada gascar, living in small troops of four or five in number, and resembling in most of its habits the animals of the next genus. 2. Propithecus, Bennett. Second upper incisor much smaller than the first. Upper canine larger than the first premolar. Muzzle rather short. Ears short, concealed by the fur. An os centrale in the carpus. Tail long. Vertebra: C7, D12, L8, S3, C28. The species are all subject to great variations in colour, which has led to much difficulty in discriminating them, and to much con fusion of synonymy. Grandidier and Milne-Edwards recognize three as certainly distinct : P. diadcma, P. verreauxii, and P. coronatus (fig. 2). Some of these are to be found in almost every part of the island of Madagascar, living in the woods in small bands of six or eight together, and feeding exclusively on buds, flowers, and berries. Their powerful hind limbs enable them to leap from tree to tree, often to a distance of ten yards, without any apparent effort, seem ing to fly through the air. When obliged to descend to the ground to pass from one clump of trees to another, they do not run on all fours, but stand erect, and throwing their arms above their heads, progress by a series of short jumps, producing an effect which is described by travellers who have seen them thus in their native haunts as exceedingly ludicrous. They are not nocturnal, but most FIG. 2. Projnthecus coronatus. From Milne-Edwards and Grandidier, Mammiferes de Madagascar, pi. 7. active in the morning and evening, remaining seated or coiled up among the branches during the heat of the day. They are naturally of a quiet and gentle disposition, and do not show much intelli gence. They are also less vociferous than the true lemurs, only when alarmed or angered making a noise which has been compared to the clucking of a fowl. Like the rest of the subfamily they never have more than one young one at a time. 3. Avahis, Jourdan. Second upper incisor larger than the first Upper canine scarcely larger than the first premolar. Muzzle very short. Ears very small and hidden in the fur, which is very soft and woolly. Carpus without os centrale. Tail long. Vertebrae : C7, Dll, L9, S3, C23. One species, A. lanigcr (Gmelin), the woolly lemur, or avahis, considerably smaller than any of the last group. It differs from them in its habits, being quite nocturnal, and not associating in small troops, but being always met with either alone or in pairs. It is very slow in its movements, and rarely descends to the ground, but when it does it walks upright like the other Indrisinse. It is found throughout the forests which clothe the mountains on the east coast of Madagascar, and also in a limited district on the north-west coast, the specimens from which locality are of smallersize and rather different in colour. II. Subfamily Lemurinae. The dentition in the adult consists of thirty-six teeth, which as usually enumerated are i, c, p%, m%. In the forepart of the lower jaw are on each side three elongated, compressed, procumbent teeth, of which the outer, usually consid ered the homologue of the canine, is larger than the others. All have long tails. Hind limbs not of tho same disproportionate size as in the last group ; and the coecum much less developed. Tarsus but slightly elongated, the os calcis being always less than one-fourth the length of the tibia. Toes of the hind feet free to the base. Habitat, Madagascar and some of the adjacent Comoro islands. This group contains the typical lemurs, or those to which the term is now chiefly restricted. Two rather aberrant members make it necessary to divide it into three genera. 1. Lemur, Linn. Upper incisors separated by an interval in the XIV. 56