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referred to three genera: (1) Anthropopithecus, which embraces the Black Apes of tropical Africa, (2) Simia, which contains the Brown Apes of tropical Asia, and (3) Hylobates, which contains the Gibbons, likewise restricted to tropical Asia.

It has been a subject of much discussion among zoologists as to which of these three forms of Simiine life comes nearest to man in structure. Some have advocated the claims of the Orang to this distinction, but it is now generally held that his black cousins of the Ethiopian Region ought to be placed at the head of the series. It has likewise been maintained by some authorities that in certain respects the Gibbons (Hylobates) come nearer to man than either of the above-mentioned forms, but this opinion has not met with general support. We will therefore commence our survey of the distribution of the Anthropoid Apes with their African representatives, the Chimpanzee and the Gorilla.

The Chimpanzee (Anthropopithecus troglodytes) is certainly widely spread over tropical Africa, but we have not as yet acquired sufficient details as to the exact limits of its distribution. Nor are naturalists at all agreed as to whether one or more species are comprehended under the name of Chimpanzee, though it is generally allowed that the Bald-headed Chimpanzee (A. calvus), a well-known specimen of which lived in the Zoological Society's Gardens for many years, must be considered distinct from the ordinary A. troglodytes. But in examining the distribution of the Chimpanzee it is hardly necessary to seek to determine this vexed question more nearly.

Commencing on the western coast of Africa, the range of the Chimpanzee appears to begin with the wooded

districts somewhat to the south of the river Gambia, and to continue all down the coast-region into Angola, south of the Congo. Here the dry and open country of south-west Africa commences, and, as the Chimpanzee is essentially a forest animal, it could not be expected to be met with farther in this direction. The Chimpanzee in its inland range appears to extend over the whole wooddistrict of the great Congo valley, and in the Niam-Niam country, perhaps, passes over into the basin of the Nile. It was heard of by Livingstone in the forests on the western side of Lake Tanganyika where it is said to be called “Soko," and the late Emin Pasha sent to England the skull of a Chimpanzee stated to have been shot by himself near Lake Albert Nyanza, which seems hardly to differ from the West African form. Whether Emin Pasha's assertion that the Chimpanzee occurs in Uganda and Unyoro up to 32° E. lat. is correct is very doubtful. It seems to have been made on native authority, and has not, so far as we are aware, been corroborated by more recent travellers. But as regards its existence in the Niam-Niam country we have Emin Pasha's express statement that he received a living specimen of the Chimpanzee as a present from one of the chiefs of that nation.1

The Gorilla (A. gorilla), which by some authors is referred to a different genus from the Chimpanzee although its general structure is not materially different, is confined to a very much more limited area than that of its smaller brother (A. troglodytes). So far as we know at present, it seems to be entirely restricted to Gaboon and the adjacent districts of French Congo. Whether the extraordinary accounts formerly given of the strength and

1 “Emin Pacha in Central Africa," p. 355.

ferocity of the Gorilla are based on fact seems to be still quite doubtful. The few specimens of this animal that have reached Europe alive have not given much support to the stories told about it.

The genus Anthropopithecus, therefore, with its two, or perhaps three, species, may be regarded as one of the most characteristic forms of the mammal-life of the Ethiopian Region to which it is absolutely confined.

Passing on to the next genus of Anthropoid Apes, we find that the Orangs (Simia) are in like manner one of the most characteristic mammal-forms of the Indian Region, to which they exclusively belong. As in the case of the Chimpanzee, there has been the same difference of opinion among naturalists as to whether there is only one or several species of Orangs. The Orang is found only in the dense forests of Borneo and Sumatra. The forms met with in these islands respectively have been treated as specifically distinct, and the Bornean form has also been divided into several species. But, on the whole, the prevalent opinion of modern writers is that there is only one variable species of Orang, which we call by Linnæus' name Simia satyrus. In Sumatra this Ape is mainly found in the lowlands of the eastern coasts of the island, in the districts of Palembang and Jambe. In Borneo it is more numerous, and has a wider range, extending all over the low forest-covered swamps between the coasts and the mountains of the interior, but in some places ascending to a considerable height in the lower hills.

The third and only remaining genus of Anthropoid Apes contains the Gibbons, or Long-armed Apes (Hylobates), which are likewise restricted to the Oriental Region, but have a much wider distribution than the Orang. The Gibbons vary much in the colour of their fur, and numerous doubtful species have been based upon such differences. The most recent authorities are not inclined to allow more than seven or eight well-marked species of Gibbons. Of them the most distinct is the Siamang (Hylobates syn. dactylus) of the Malay Peninsula and Sumatra, which has the second and third toes of the feet joined together by a thin web of skin, and has other slight peculiarities, which have induced some naturalists to place it in another genus. But this seems to be quite unnecessary. The remaining typical Gibbons are thinly distributed over all the three great islands of the Malay Archipelago, Sumatra, Java, and Borneo, extending into the Sulu group between Borneo and the Philippines. On the continent they range high up the Malay Peninsula, even so far north as Assam and Bhootan, where they are represented by the Hoolock (H. hoolock). They are also found in Siam, Cambodia, and Annam, and one species (H. hainanus), has been discovered in the Chinese island of Hainan.

Thus of the three generally recognized genera of Simiidæ, or Anthropoid Apes, one is of the Ethiopian, the two others of the Oriental Region.

We now come to the second family of Catarrhine Monkeys, the Cercopithecidæ, or what are usually called the Old World Monkeys. Of these, about one hundred and twenty species are known, divisible into about nine wellmarked genera. Most of these monkeys, as we shall show, belong to the Oriental and Ethiopian Regions, but the genera which inhabit these Regions respectively are quite distinct. Two genera alone, Macacus and Semnopithecus, have representatives within the limits of the Palæarctic Region.

The Langurs (Semnopithecus) of the Oriental Region, which we will take first of the group, remarkable for their slender body and the excessive length of their tails, are distributed over Southern Asia and the adjoining islands of the Malay Archipelago, and are numerous in species, as many as twenty-nine or thirty being of probable validity. Dr. Blanford describes as many as fourteen of them in his “Fauna of British India," as met with within the limits of India, Ceylon, and Burma. Of these, one, S. schistaceus, has mounted high into the Himalayas, where it ascends to an elevation of 10,000 feet and is never met with below 5000 feet. But this species is undoubtedly derived from the plains of India, being a very close ally of S. entellus, which has a wide distribution over the northern provinces. Another well-marked species of this genus is found high up in Eastern Tibet and North-western China, where it inhabits the mountain forests and has been named S. roxellanæ from its conspicuous turned-up nose. Borneo, Sumatra, and Java, have each of them distinct species of this wide-spread genus.

Closely allied to the Langurs (Semnopithecus) is the very curious Long-nosed or Proboscis-monkey of Borneo, which seems to be confined to the lowlands near the mouths of the rivers in Sarawak and the adjoining districts of that island. It is the sole representative of the genus Nasalis.

Passing back to the Ethiopian Region, we find in the place of Semnopithecus and Nasalis the genus Colobus, remarkable for the absence of a thumb on its hand, but in other respects closely allied to its Asiatic brethren. About ten species of Colobus are generally recognized by naturalists. They are distributed all over the forests of tropical Africa, being, perhaps, most abundant on the west

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