Fauna : Mammals 



Of the true porcupines there are two kinds, the common 

 species {Hystrix cristata\ which inhabits Southern Europe, 

 North-east and West Africa ; and the Brush-tailed Porcupine, 

 Atherura africana. The last-named is easily distinguished from 

 the first, because it is a smaller animal, the spines are less 

 markedly developed, and the tail is much longer and tipped 

 with a bundle ot flattened quills. Atherura is one of the 



268. BRUSH-TAILKD PORCUPINE (ATHERURA 



numerous genera of mammals and birds which are common 

 to West Africa and South-eastern Asia, though absent in the 

 modern period from the intervening regions of East Africa 

 and India. 



Another family of porcupine-like rodents exhibits a different 

 relationship in African geographical distribution. This is the 

 group of Octodonts, which is at the present day represented 

 by numerous genera and species in South America and the West 

 Indies, and by two genera in Africa — Pteromys and Thryriomys. 



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