CHAP. XI.] THE ETHIOPIAN REGION. 261 



region, and it suggests some curious speculations as to the former 

 history of that region, a subject which must be deferred to the 

 latter part of this chapter. In none of the other great tropical 

 regions does it occur, that the largest portion of their area, 

 although swarming with life, yet possesses hardly any distinctive 

 features except the absence of numerous types characteristic of 

 the other sub-regions. 



Plate IV. — Illustrating the Zoology of East Africa. — Although 

 this sub-region has so little speciality, it is that w^hich abounds 

 most in large animals, and is, perhaps, the best representative of 

 Africa as regards zoology. Some of the most distinctive of African 

 animals range over the whole of it, and as, from recent explora- 

 tions, many parts of this wide area have been made known to the 

 reading public, we devote one of our plates to illustrate the 

 especially African forms of life that here abound. The antelopes 

 represented are the koodoo {Tragelaphus streps' ceros) one of the 

 handsomest of the family, which ranges over all the highlands 

 of Africa from Abyssinia to the southern districts. To the left 

 is the aardvark, or earth pig, of North Eastern Africa {Orydcropus 

 cethiopicus) which, to the north of the equator in East Africa, 

 represents the allied species of the Cape of Good Hope. These 

 Edentata are probably remnants of the ancient fauna of Africa, 

 when it was completely isolated from the northern continents 

 and few of the higher types had been introduced. The large 

 bird in the foreground is the seci'etary-bird, or serpent-killer 

 {Serpentarius reptilivorus), which has affinities both for the birds- 

 of-prey and the waders. It is conmion over almost all the open 

 country of Africa, destroying and feeding on the most venomous 

 serpents. The bird on the wing is the red-billed promerops 

 (Irrisor erythrorkynchus), a handsome bird with glossy plumage 

 and coral-red bill. Tt is allied to the hoopoes, and feeds on 

 insects which it hunts for among the branches of trees. This 

 species also ranges over a large part of east and central Africa to 

 near the Cape of Good Hope. Other species are found in the 

 west; and the genus, which forms a distinct family, Irrisoridce, is 

 one of the best marked Ethiopian types of birds. In the distance 

 is a rhinoceros, now one of the characteristic features of African 



