318 TROPICAL NATURE, AND OTHER ESSAYS. 



groups of mammalia. Such are the bears, which 

 range over the whole northern hemisphere, and as far 

 south as Sumatra in the eastern and Chili in the western 

 hemisphere, yet they are totally wanting in Tropical 

 and South Africa ; the deer, which are still more 

 widely distributed, ranging all over North and South 

 America, and over all Asia to Celebes and the Moluccas, 

 yet they are totally absent from the Ethiopian region ; 

 goats and sheep, true oxen (Bos), and true pigs (Sus), 

 are also absent ; though as to the last there is some 

 doubt, certain wild pigs having been observed, though 

 rarely, in various parts of Tropical Africa, but it is not 

 yet determined whether they are indigenous, or escaped 

 from domestication. The absence of such wide-spread 

 families as the bears and deer is, however, most im- 

 portant, and must be taken into account when we 

 come to consider the geographical changes needed to 

 explain the actual state of the Ethiopian fauna. 



The birds are not proportionately so peculiar, yet 

 there are many remarkable forms. Most important are 

 the plantain-eaters, the ground-hornbills, the colies, and 

 the anomalous secretary-bird ; while among character- 

 istic families there are numbers of peculiar genera of 

 flycatchers, shrikes, crows, sun-birds, weaver-birds, 

 starlings, larks, francolins, and the remarkable sub- 

 family of the Guinea-fowls. There are not such 

 striking deficiencies among birds as among mammals, 

 yet there are some of importance. Thus, there are no 

 wrens, creepers, or nut-hatches, and none of the wide- 

 spread group comprising the true pheasants and jungle 

 fowl a deficiency almost comparable with that of the 

 bears or the deer. Among the lower vertebrates there 



