Part 16

This genus contains the typical Lemurs, in their most restricted sense. They are characterised by having a very {66}Fox-like head, and an elongate and tapering face, shelving on each side of the nose. A long fringe of hair surrounds their chin and cheeks. They have all large and tufted ears, and large eyes, with superciliary ridges rising higher than the forehead. Their tail is always half as long as the body at least. The fore-limbs are somewhat shorter than the hind-limbs, and both the wrist and ankles are haired. The ankle is not elongated, nor is the great toe as large as in the next family--the Indrisinæ. On the outside of the palm of the hand and under the base of the fingers are situated fleshy pads, giving them greater grasping power. The True Lemurs have only one pair of mammæ, which are situated on the breast.

In the skull the facial region is much elongated, its measurement from the anterior margin of the orbit forward being greater than the longitudinal diameter of the orbit, and the space between the eye-sockets is narrow and depressed. The bony palate is short, extending back only to the posterior end of the median molar. The posterior portion of the ear-capsules (the mastoidal and squamosal regions) is not inflated--a character which separates this genus from Galago. The pre-maxillary bones are large and protrude in front, if the skull be viewed from the side. The angle of the lower jaw is not produced downwards and backwards. In some species a large maxillary sinus projects into the anterior part of the orbit; in some also the foramen rotundum does not coalesce with the sphenoidal fissure (see page 11), but has a distinct opening. The teeth are of the normal number, namely thirty-six. In the upper jaw the incisors are small, sub-equal, and situated anteriorly to the canines and are not in contact with each other, or with the latter. The canines are very large, tusk-like, and set in an excavated notch on the jaw. All the pre-molars {67}have one main cusp to the outside; the anterior pre-molar, however, has a supplementary minute front cusp, while the median has in addition one large interior cusp; both it and the posterior pre-molars are vertically taller than their anterior fellow. The molars have two inner cusps, and two main outer cusps with a supplementary minute fore cusp, as well as two cusps on the ridge joining the fore and hind outer cusps; the posterior molar--the smallest of the three--is, however, larger than the posterior pre-molar, and has only the front inner cusp and no supplementary external cusp. The lower jaw shows a gap between the canine and the anterior pre-molar. The anterior pre-molar, which is vertically taller than the rest, is edged and cutting, taking the place of a tusk; the anterior and median pre-molars are also separated by a small space; the latter, which is equal in vertical height to the posterior, has an inner cusp and a low cusped heel. The molars have two outer main cusps, of which the front one is more developed than the hind one, and two inner cusps, often with an intermediate cusp between them; the pair of fore and the pair of hind cusps are joined by transverse ridges, and the two outside cusps by a backwardly directed semicircular ridge; the posterior molar is four-cusped.

The dorsal and lumbar vertebræ together do not exceed twenty in number.

The hind portion of the cerebellum is large, which points to intellectual inferiority in the True Lemurs as compared with the Apes.

The species of this genus are all confined to the island of Madagascar and some of the smaller adjacent islands. They are gregarious, living in large companies in the forests, feeding on fruits, insects, and such small animals, birds, and lizards {68}as they may capture. Like the Howlers of S. America and the Gibbons of the East Indies, they are very noisy. Their agility is wonderfully great, and is displayed chiefly in the evening. During the brighter hours of the day they sit somnolent, either alone with their heads buried between their arms, their tail coiled round the neck, or in twos or threes embracing each other with their arms. In walking they use their fore-limbs less as hands, and more as feet than do the members of the next family--the Indrisinæ--both when on the ground, as well as when climbing among the trees.

I. THE RUFFED LEMUR. LEMUR VARIUS.

Lemur macaco, var. Schreber, Säugeth., p. 142, pl. 40 B (1775).

Lemur macaco et L. ruber, Geoffr., Ann. Mus., xix., p. 159 (1812).

Lemur varius, Is. Geoffr., Cat. Méth. Primates, p. 71, no. 2 (1851); Schl., Mus. Pays. Bas., vii., p. 301 (1876); Milne-Edwards et Grandid., H. N. Madag., Mamm., Atlas, pls. 123-129 (1690).

(Plate VII.)

CHARACTERS.--Face and top of head black; a stripe over the eyes, ridge of nose and tip of nostrils, creamy-white; a patch on the shoulder, the inside of the fore-legs, the inner surface of body, a patch on the front of the thighs, the inner side of the limbs, and the feet, black; tail black, washed with white on the upper surface; rest of body creamy-white.

PLATE VII.

{69}The Ruffed or Variable Lemur derives its name from the remarkable variability of its external markings: so much is this the case, indeed, that not a few of them have been described as distinct species. This variability appears to be entirely individual, and is by no means constant. The Black-mantled variety has the back of the neck, the shoulders and interscapular region entirely black. Another form has the ears, the ruff, and a bar across the muzzle extending over and in front of the eyes, joining the ruff, pure white; the fore-arms, legs, a bar across the buttocks joining the thighs greyish-white; face, legs, and tail black; a ring encircling the body like a belt between the fore- and hind-limbs, yellowish-white; rest of body dark reddish-brown. A third variety has the ears, ruff, and outer side of the arms and legs pure white; the flanks rusty-red, the rest of the body black.

THE RED-RUFFED LEMUR (L. ruber) is a very well-marked variety of the same species, and may easily be recognised by the ears, ruff and whole upper surface of body being dark rusty-red, with the outer surface of thighs and legs white; or, the ears, ruff and whole upper surface (except a white patch on the back of the neck) may be dark brown, with a white garter on each ankle; otherwise it may be entirely black. It is this variety which we have figured on Plate VII.

DISTRIBUTION.--Throughout the north-east of Madagascar.

HABITS.--The Ruffed Lemur, called by the natives "Varikossi," has a loud, harsh and powerful voice, which can be heard for a long distance.

II. THE BLACK LEMUR. LEMUR MACACO.

Lemur macaco, Linn., S. N., i., p. 44 (1766); Schl. Mus. Pays. Bas., vii., p. 302 (1876); Milne-Edwards et Grandid., H. N. Madag., Mamm., pls. 131, 132 (1890).

Lemur niger, Schreb., Säugeth., pl. 40 A (1775).

Lemur leucomystax, Bartlett, P. Z. S., 1862, p. 347, pl. xli. (female).

Varecia nigra, Gray, P. Z. S., 1863, p. 136.

{70}CHARACTERS.--Ears tufted, with long hairs continuing down the side of the neck to the angle of the mouth.

MALE.--Entirely black.

FEMALE.--Formerly described as a distinct species, and known as the White-whiskered Lemur (L. leucomystax). Face and lips black, darkest on the nose, round the eyes and hinder part of the head; forehead blackish-grey; whiskers and ear-tufts white, almost concealing the ears. General colour of body rich ferruginous brown, darker on the middle of the back; arms, legs and neck reddish-yellow; tail whiter; throat, under side of body and inner side of limbs creamy-white.

There is a considerable amount of variation in this species. Some individuals have the lower back and base of tail white; the belly greyish-white, the feet brown, and the toes black. In others the black frontal spot is wanting, the back of the head being reddish-white; the basal half of the tail is dark orange-red, remainder of the body rich rusty-brown. On the fore-arm is a cluster of stiff hairs, which occurs in association with a large underlying sweat-gland, whose function is not yet understood.

DISTRIBUTION.--The north-west coast of Madagascar.

HABITS.--The special habits of this species of Lemur are unknown, but in all probability they agree with those of the group in general, as given under the heading of the genus. It is said to utter a coarse grunting call-note.

The young males are born black like the father, and the young females have the colour of the mother. Dr. Sclater has observed that in specimens in confinement in the Zoological Gardens, in London, the female carried her young one transversely across her belly, its long tail passing round her back and then round its own neck.