Page:Encyclopædia Britannica, Ninth Edition, v. 2.djvu/168

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154 APE [CEBID.B. red or golden hair on the flanks. There is, however, so much individual variation, or so many local varieties, that the species are as yet very little determined. The sexual difference in colour is great in one species the male being deep black, and the female pale straw colour. Amongst the species described may be named Seniculus, Ursinus, Garaya, Rufimanus, Niger, Villosus, and Palliatus. The third sub-family of American apes is composed of very peculiar forms, termed Sakis, which are subdivided into two genera, Pithecia and Brachyurus, according as the tail is long or short. They are together distinguished from all the Cebidce yet noticed, by not having the tail prehensile, even when long ; also by having the lower incisor teeth inclined forwards, instead of standing up vertically. Great differences as to the hair exist in this group, some having long hair over the whole body, others on the head, and others on the chin and cheeks, while a species of Brachyurus (B. calvus) has the head naturally bald. Of the genus Pithecia, the following species have been de scribed : Leucocephala, Rufiventer, Monachus, Satanas, Chiropotes, Albinasa, and Chrysocephala. Of Brachyurus, besides Calvus, only Rubicundus has as yet been described. The Brachyuri are the only American apes with short tails, and they are the least arboreal, frequenting bxishes rather than trees. They are very timid creatures, and gentle, and rather slow in their movements. It is but very rarely that any of the Pitheciinoe have been brought to Europe alive. J FIG. 10. The White-cheeked Sapajou (Cebtis leucogenys). From Pro. Zool. Soc. 1865, pi. 45. The next sub-family, Nyctipithednaz, contains three genera, which have a long but not prehensile tail, fairly- developed thumbs, and vertical lower incisor teeth. These animals are, in part at least, insectivorous. The typical genus, Nyctipithecus, contains only the night-apes, or douroucoulis (N. felinus, lemurinus, oseryi, rufipes, and Spixii), which have, in harmony with their noctural habits, enormous eyes. The orbits, though closely approximated, are nevertheless separated by a com plete bony system. The head is rounded, but greatly drawn out posteriorly. The nostrils are rather approxi mated. The beautiful little squirrel monkey, or Saimiri, and three allied species (Ch. ustus, entomophagus, and CErstedii), form the genus Chrysothrix. They are distinguished from all other apes by the great backward prolongation of the bony cranium, the orbits of which, though smaller than those of Nyctipithecus, are, nevertheless, separated, but by an imperfect bony septum. A few other kinds of American apes, together forming the genus Gallithrix, somewhat resemble the night apes, but FIG. 11. Tho Lemurine Night Ape (Nyctipithecus lemurinus). From Archives du Museum, voL iv. pi. 2. that the eyes are much smaller, and the nostrils wider apart. They differ from Chrysothrix in having small canine teeth, and the tail furnished with long hairs. The species of this genus are Moloch, Personatus, Amictiis, Gigo, Melanochir, Discolor, Donacophilus, Ornatus, and Castaneoventris. There remains now to notice but one more group of apes, those which have been classed as the last sub-family the Hapalince, marmosets, or oustitis. These animals are so different from all that have gone before that there is probably almost as much to be said for ranking them as a family by themselves as for considering them, as is here done, but a sub-family. Much, however, as they differ from all the other apes, they manifest their affinity to the rest of the Cebidce by the absence of the meatus auditorius ex- ternus, and by the presence of the extra premolar tooth on each side of each jaw. They have, however, the same total number of teeth as have man and the Simiadce. This is occasioned by their not possessing any third true molar, either above or below ; so that their dentition thus differs from that of the Old World apes in two points, instead of only one. In all the apes we have yet noticed, except the orang, the hallux is well developed, while in the mar mosets it is exceedingly small. The hand, however, is yet more exceptional, as the thumb is not at all opposable, while, in common with all the other fingers, it is furnished with a long, curved, and pointed claw. The tail is not prehensile, but long, and furnished with more or less elongated hairs. In several, and especially the more commonly seen species, a tuft of long hairs projects out wards and backwards on each side of the head. These animals are very small, the largest being about the size of squirrels. They are, like squirrels, active in their motions, and arboreal in their habits, living in small troops, and eating insects as well as fruit. They are very difficult to keep in captivity in northern climates ; but, nevertheless,

they have occasionally bred in England, bringing forth as