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 which 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 (T’ragelaphus strepsiceros) 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 (Orycteropus 
ethiopicus) 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 secretary-bird, or serpent-killer 
(Serpentarius reptilivorus), which has affinities both for the birds- 
of-prey and the waders. It is common 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 erythrorhynchus), a handsome bird with glossy plumage 
and coral-red bill. It 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, I7risoride, is 
one of the best marked Ethiopian types of birds. In the distance 
is a rhinoceros, now one of the characteristic features of African 
