Imágenes de páginas

The second peculiar Rodent of family rank is Lophwmys, a curious arboreal animal allied to the rats, but differing from them in several anatomical features, and in having a long crest of hair upon the back. Only one species is known, which is restricted to North-East Africa.

The distribution of a third Ethiopian family of Rodents (Octodontidm) is particularly interesting, as it is represented in South America by a considerable number of genera, and is not found elsewhere except in the Ethiopian and on the borders between the Ethiopian and Palsearctic Regions. There are four African genera of this family, each with a single species, so that in the Old World the group appears to be in a state of decay. The only light thrown on this curious case of discontinuous distribution is the occurrence of a fossil genus (Pellegrinia) allied to the African forms in the Pleistocene beds of Sicily. This indicates that members of this family once had a wider distribution northwards than what they now retain.

The Carnivora are well represented in the Ethiopian Region. This is especially the case with the family of Civets (Viverridx), only found elsewhere in the Palsearctic and Oriental Regions. Out of a total number of seventeen genera, three only are found outside this region, and out of the remaining fourteen, six are confined to the island of Madagascar.

The Aard-wolf (Proteles), which is so distinct from its fellow Carnivores as to be allowed to constitute a family of itself (Fig. 17, p. 95), is restricted to the Ethiopian Region, and of the Hyenas (Hymnidm), only one of the three species strays outside its limits, into the western borders of the Oriental Region.

Another remarkable fact about the Ethiopian Carnivora is the entire absence of the otherwise widespread family of Bears (Ursidm). This group has existed in Europe since the time when the Upper Pliocene beds were laid down, and remains of Bears have been also found in the Siwalik deposits of India, which are possibly

[graphic][merged small]

of even greater age. It seems, therefore, very strange that the Bears should never have reached Africa, when so many of the other genera found in the same deposits have managed to do so.

The Insectivora of the Ethiopian Kegion are fairly numerous, and show considerable specialisation. Out of the six Ethiopian families three are not found elsewhere, and one of the others only extends into the Palaearctic Region as far as Northern Africa. This is the family of elephant-shrews (Macroscelidm).

The Bats of this Region present few particular features of interest, belonging nearly all to widely spread genera of widely spread families. Among those that are peculiar the most important is Epomophorus, containing eight or ten species of large fruit-eating bats, with long rather horse-like heads, and expansible and peculiarly folded lips. The Epomophori seem to take the place, in Africa, of the genus Pteropus, which, although represented by several species in Madagascar, and even in the Comoros (which are separated from the mainland by only a comparatively narrow strait), is entirely absent from the African mainland itself.

Among the Lemurs we have two families, one containing only a single species (Chiromyicke) confined to Madagascar, the other (Lemuridm) containing a large number of genera, of which ten are confined to Madagascar, two are found on the mainland of Africa, and the other two in the Oriental Region.

The Quadrumana of the Ethiopian Region, which are entirely absent from Madagascar, belong to two families, both of them shared with the Oriental. The genera, however, six in number, are all without exception confined to this Region In the first place this Region is the only home of the Gorilla and Chimpanzee (Fig. 18, p. 97), two of the Apes most nearly allied to Man in structure, and usually placed at the apex of the mammalian series. The Colobs, or Thumbless Monkeys (Colobus), represent the Langurs (Semnopithecus) of the Oriental Region in Africa, and number some ten or twelve species. The long


Fig 18.—The Chimpanzee.
(Anthropopitltecus troglodytes.)

tailed Cercopitheci, or Guenons, are essentially arboreal, and are spread all over tropical Africa where trees are found. They are very numerous, and from thirty to forty species have been described, some of them, such as the Diana Monkey (Cercopithecus diana) and Brazza's Monkey (C. brazzm) remarkable for their beautifully coloured fur. Intermediate between the Guenons and the Macaques of the Oriental Region are the Mangabeys (Cercocebus), of which some six species are recognized. Finally, the terrestrial Baboons (Theropithecus and Cynocephalus) close the Ethiopian series with some eight or ten species.

Summarizing these results, therefore, we find that the Ethiopian Region is characterized by the exclusive possession of eleven families of mammals, namely—

Orycteropodidae (Aardvark), Protelidse (Aard-wolf),

Hippopotamidea (Hippopotamus), Potamogalidae (River-shrew),

Giraffid® (Giraffe), Centetidas (Tenrec),

HyracideB (Rock-coney), Chrysochloridse (Golden-mole),

Anomaluridse (Anomalure), Chiromyidss (Aye-aye),
Lophiomyidss (Crested Tree-rat),

and by the presence of about ninety-nine endemic genera.

On the other hand, among a considerable number of families not represented in this Region, the following five are all widely spread elsewhere, and may therefore be considered as typical "lipotypes" of the Ethiopian Region:—

Cervidw (Deer). Ursidee (Bears).

Tapiridsa (Tapirs). Talpidae (Moles).

Castoridffl (Beavers).

Section III.—Subdivision Of The Ethiopian Region

In dividing the Ethiopian Region into Sub-regions, it must be always remembered that one of the Sub-regions far predominates over the others in speciality and distinct

« AnteriorContinuar »