Liberia <*- 



sheep cross the Sahara Desert in their distribution, unless it 

 be up the course of the Nile.^ I do not myself see any reason 

 for deriving these two breeds of maned and fat-tailed sheep 

 from separate wild ancestors. The development of fat at the 

 base of and along the tail is no doubt partly a specialisation 

 which arose in arid, semi-desert countries in the north-east of 

 Africa, and the earliest domestic breed of sheep to enter the 

 Dark Continent was probably of the maned type, with a simple 

 tail. Likewise the mane along the throat may give place to a 

 dewlap, or the dewlap may revert to a mane. Some of the 

 fat-tailed sheep have a tendency to drooping ears which is never 

 seen in the maned breed. 



On the whole I can see no reason to suppose that these 

 African breeds of sheep may not have been derived from the 

 same ancestor as gave rise to the woolly sheep of Europe and 

 Asia ; and the existing wild species which comes closest in 

 coloration, shape of horns and other characteristics to all the 

 existing breeds of domestic sheep is the wild mouflon of Corsica 

 and Sardinia. There are probably only two difficulties which 

 stand in the way of our considering this animal to be the 

 ancestor of Ovis aries in all its known forms, and that is the 

 tail and the absence of horns in the female. The tail of all 

 breeds of domestic sheep {Ovis aries) in their natural condition 

 is long, descending almost to the level of the hocks. Now the 

 only existing wild sheep at the present day which has a long 

 tail is the already mentioned audad of North and North-east 

 Africa, which for reasons not necessary to set forth in detail 

 cannot possibly be regarded as the ancestor of Ovis aries. But 

 of all the true wild sheep ^ of the present day the one that has 



' They have been introduced by the Libyans to Timbuktu and the northern 

 bend of the Niger. 



' Excluding the barhel sheep {/'scmiois) of Central Asia, in which the tail 

 is sometimes six inches in length. 



918 



