44 . THE MAMMALS OF ETHIOPIAN AFRICA 



That the fauna of the forest-tract of Africa is intimately related to those of Ceylon, 

 southern India, and the Malay countries has been long familiar to naturalists, but 

 it is only recently that a satisfactory explanation of the fact has been suggested. 

 This is due to Dr. Arldt, who points out that when the extinct Siwalik fauna 

 migrated from India to Africa during later Pliocene time, probably by way of 

 Baluchistan, Persia, and Arabia, or perhaps by a submerged line now represented 

 by Socotra, the route must have been along a forest-tract, as otherwise animals 

 like chimpanzis and okapis could not have formed part of the company, and of 

 these ancient forests we have evidence in the silicified tree-trunks of the Punjab, 

 Baluchistan, Syria, and Egypt. As the result probably of secular desiccation, the 

 country subsequently assumed a more or less desert character, with the result that 

 the forest animals were compelled to retreat to districts suitable to their habits ; 

 in other words, to Ceylon, Malaya, and the equatorial forests of Africa. In this 

 way, and in this way only, can be satisfactorily explained the fact that pigmy 

 squirrels and chevrotains are common to the African forest-region and Indo- 

 Malaya, and that the pottos of the one tract are represented by the lorises of the 

 other. The discovery that so many of the African types formerly supposed to be 

 confined to the west coast really range far to the east has greatly simplified the 

 distributional problem of the animals of Africa. 



On the Loango coast two types of what is called veldt are met with ; the one 

 consisting of open, grassy plains, with sparsely distributed, flexible grasses, of not 

 quite a man's height, which permit a view of the country. In the other type the 

 plains are covered with closely growing, stiff, strong grasses, which make it 

 difficult or impossible for the traveller to leave the beaten path. The main mass 

 of vegetation in the open grassy plains consists of sweet grasses about 3 feet in 

 average height ; while the stiff grasses on the smaller plains rise to a height of as 

 much as a dozen or even sixteen feet. The bright refreshing green of the meadows 

 of Europe is never seen on the African veldt, even during the time of the most 

 abundant growth of grass, because the quickly-growing grass is always mixed with 

 dried, broken, or spear-like sprouting blades, which impart a yellowish or brownish 

 tinge to the entire green area. Among the larger trees of the plains, the most 

 famous and best known is the baobab, or monkey-bread tree (Adansonia digitata), 

 a species restricted to the open country. Generally a well-grown tree of gigantic 

 size, the baobab is distinguished by the disproportionate, it might even be said 

 ungainly, thickness of the stem and branches. In shape it generally resembles a 

 large oak, although, as a rule, it is not so gnarled and the branches are less sharply 

 curved. The massive unbranched stem may be either as cylindrical as a column, 

 and carry its crown of foliage at a considerable height, or may be short, and studded 

 with knots, and dividing into a number of equal-sized branches close above the 

 ground. In other cases the stem gives off its branches near the ground, and 

 remains distinguishable for two-thirds the height of the tree as its principal part. 

 During the dry season the baobab sheds its leaves, its vigorous growth being due 

 to the soft, sappy wood, which acts as a water-reservoir. 



On the eastern side of the tropical portion of the country the plains consist 

 chiefly of grass, low shrubs, and thorn-bushes ; a mimosa of some kind or other 

 rising, with its doubly pinnate leaves, every few yards. Whether these 



