Page:Encyclopædia Britannica, Ninth Edition, v. 7.djvu/289

271 DISTRIBUTION 271 of toads. There are also three peculiar families of fresh water fishes. It is impossible to give any idea of the special features presented by the insects and land-shells without going into details which would be out of place in such a sketch as we are here giving. In both these groups Africa is fully as rich as the other tropical regions, and exhibits perhaps more peculiar features than among the higher animals. We must, however, just mention the remarkable absence from the Ethiopian region of certain groups of Mammalia which abound in the countries to the north and east of it, as this phenomenon has an important bearing on the probable origin of the fauna. The most striking of these deficiencies are the two families of the deer and the bears, j which abound over. the whole northern hemisphere, in tropical Asia and the Malay islands, and even in North Africa, but are both entirely unknown over the whole Ethiopian region, as are, among smaller groups, the goats and sheep, the true oxen, and the mole family. Among birds such wide-spread groups as the wrens (Troglodytidce), dippers (CiiicliJfje), and the true pheasants are also entirely wanting.- The exceeding speciality of the forms of life which are Btill found in the Ethiopian region is well shown by the fact that there are about 24 family groups of vertebrate animals which are entirely confined to it, while two-thirds of its genera of Mammalia, and three-fifths of the genera of birds, are also peculiar. Subdivisions of the Ethiopian Region. The most remarkable of these is undoubtedly that comprising Madagascar and the Mas- carene islands, a district which contains so many singular forms j of life that it has been proposed by some naturalists to make it one of the primary zoological regions. The peculiarity of these islands is twofold, consisting as much in the absence of a great number of the most characteristic African forms as in the possession of others entirely peculiar. The apes and monkeys, the large Carnivora, the zebras, giraffes, antelopes, elephants, and rhinoceroses, and even such smaller forms as the porcupines and squirrels, are entirely wanting. Yet Madagascar possesses a host of remarkable Lemur- .idee, consisting of 7 genera and 35 species, all of which are peculiar; a peculiar family of Jnsectivora, comprising 5 genera and 10 species; a peculiar family and 5 peculiar genera of small Carnivora ; and 3 peculiar genera of Muridce. Efen among birds, so much better able to traverse a narrow sea, there are some curious deficiencies, the families of woodpeckers (Picidce), honey-guides (Indicatoridce) , barbeta (Megalcemidce), plantain - eaters (Musophacjidce), colies (Collides), hornbills (Buccrotidcc), and mockers (Irrisoridcc) all abundant ou the opposite coast of Africa being entirely wanting. Yet birds are suiliciently abundant, nearly 120 species of true laud- birds being known, while there are no less than 33 genera which are altogether confined to Madagascar and the Mascarene islands. If we consider the species, the peculiarity is even more remarkable, there being more than a hundred which are peculiar to about a dozen which are found elsewhere. These numbers, however, by no means fairly represent the special character of the Mascarene bird- fauna, which consists in the anomalous character of many of the genera, so that it is to this day a matter of dispute among ornitho logists in what families a considerable number of them should be classed. Among these anomalous genera are Mcsites, Tylas, Ar- tamia, Calicalicus, Euryceros, Philepitta, Leptosomus, Atelornis, and several others. Taking all these facts into consideration, we arrive at the conclusion that the fauna of Madagascar is more pecu liar than that of any other single island ou the globe. The reptiles of Madagascar are less known, but they exhibit some remarkable peculiarities. Many African groups are wanting, others are represented by peculiar genera, while a considerable number of groups have their nearest allies, not in Africa, but in tropical Asia and in South America. Among insects the butterflies are allied to those of Africa ; but the beetles, like the reptiles, show many cases of aifinity with the Malay islands and South America, though the majority are perhaps related to true Ethiopian forms. The continental part of the Ethiopian region appears to have no subdivisions clearly marked out by natural barriers, yet it may be divided into three tolerably well-defined sub-regions in accordance with differences of climate and vegetation. These may be termed the sub-region of open plains, the forest sub-region, and the south temperate sub-region. The first comprises the greater part of Central and East Africa, and a northern belt from Senegambia through Lake Chad to Abys sinia, while it extends to the Atlantic coast from Angola to Damara Land. This extensive district may doubtless be further sub- divided, but it exhibits throughout the main features of Central African zoology as distinct from that of West and South Africa. It9 zoological characters are negative rather than positive, as it lias very few peculiar groups ; but all the great African Mammalia abound, and a greater variety of antelopes are found here than iii the other sub-regions. The West African or forest sub-region extends from the Gambia to the Congo, and inland to the sources of the Nile and the western watershed of the great lakes. It is characterized generally by a luxuriant forest-vegetation, and it possesses many peculiar animal forms. Here we find the gorilla and chimpanzee, a great variety of monkeys, and two peculiar genera of lemurs, as well as some re markable genera of Insectiwra, Viverridce, arid Tragulidcc. It is the home of the gray parrots (Psittacus), the typical plaintaiu- eaters (Sfusophaga), one of the Eastern group of ground thrushes (Pitta), and many peculiar genera of passerine birds. Reptiles are very abundant, no less than 13 genera of snakes and 3 of lizards being peculiar to this sub-region. As is always the case in tropical forest-districts, insects are especially numerous, of large size and brilliant colours. The South African or extra-tropical sub-region, though qiiito open to the central districts and to a large extent overrun with the same fauna, yet presents so many peculiarities as to indicate, pro bably, a former southward extension of the continent. We find here 3 peculiar genera of Vivcrridcc, the remarkable Protcles, pecu liar Canidcc and Mustelidce, many peculiar rodents, including Bathycrycs (one of the mole-rats), Pctromys (one of the spiny-rats), and Pedctes (the Cape-hare). There are also some peculiar genera of birds, among which are a sun-bird, 2 weaver-birds, 3 larks, and a curious woodpecker (Geocolaptes). Reptiles are still more pecu liar, 4 genera of snakes and 10 of lizards being almost or quite restricted to this limited district. Insects, too, are very remark able, there being 7 peculiar genera of butterflies, and a host of beetles which are either quite peculiar or have their nearest allies in Madagascar, in India, or America. This remarkable and isolated fauna must be considered, in connection with the wonderful Cape flora so much richer and more isolated than that of any other part of Africa as indicating important changes in the past history of this part of the globe. III. The Oriental Region. The Oriental region is wholly tropical, but is of smaller extent than the Ethiopian. It is very largely covered with forest-vegetation, and is much broken up into islands and promontories, conditions so favourable to animal life as fully to compensate for its smaller area. In the larger Mammalia there are many resemblances between the Oriental and Ethiopian regions. Both have anthropoid apes, elephants, rhinoceroses, large felines, buffaloes, and an abundance of civets. But the Oriental region abounds in deer and bears, it has many remarkable Insectivora, the Malay tapir, and many wild cattle. It has also a great number of characteristic forms of life. It has 6 peculiar genera of apes, and 3 of lemurs ; 5 of Insectivora, among which are two peculiar families, GaleopithecidoB and Tupaiidce ; 12 of Viverridoe ; 1 one of Canidae ; 5 of Mustelidce ; 2 of Ursidce ; 1 of Tragulidce ; 1 of Ccrvidce ; 4 of Bovidce ; and 5 of Rodents. The birds of this region are exceedingly abundant, varied, and remarkable. Among them are 3 peculiar families of passerine birds the hill-tits (Liotrickidce), the green bulbuls (Phyllornithidce), and the gapers (Eurylcemidce) ; while the babblers (Timaliidce), the fruit-thrushes (Pycnonotidoe), and the king-crows (Dicriiridce) are far more abundant than in the adjacent regions. Tits, flycatchers, crows, sun-birds, starlings, kingfishers, pigeons, and pheasants are also very abundant, and are represented by many remarkable forms. More than 340 genera of land-birds inhabit the region, of which number 165 are peculiar to it. Reptiles are very abundant. Three small families of snakes are peculiar, and there are a large number of peculiar genera both of snakes and lizards. Insects are exceedingly varied and beautiful, especially in the Himalayas and in the Malay islands, Among butterflies the Danaidce are very abundant, while the true Papllios are perhaps finer than in any other part of the