-•) Fauna : Mammals 



those of Southern and Eastern Africa, Syria and Arabia, which 

 had taken, like the baboon, to living amongst rocks instead 

 of trees ; but even the rock-dwelling hyraxes are able to climb, 

 being able, like their arboreal congeners, to ascend almost per- 

 pendicular surfaces by the sucker-like action of the naked foot- 

 pads on the under-side of the paws. 



Procavia dorsalis is perhaps the largest of the hyraxes, 

 the size of a big domestic rabbit. It is covered with long hair, 

 grey towards the tip, so that the animal has a somewhat 

 grizzled appearance. Along the lower part of the back, just 

 over the spine, is a long patch of white hair, such as is met 

 with in most of the tree hyraxes. This white mark, which 

 covers a gland in the skin, is particularly noteworthy In Procavia 

 dorsalis, the common tree hyrax of West Africa. When 

 the animal is excited it makes all its hair stand out rather 

 like a porcupine's quills, and the white hairs above this gland 

 then part somewhat from side to side, showing a patch of 

 bluish naked skin. The uses of this gland, so strangely placed, 

 do not seem yet to be known. 



Procavia stampflii, if it be a valid species or sub- 

 species, is distinguished from P. dorsalis by being of smaller 

 size. 



These tree hyraxes differ from the steppe and rock- 

 haunting members of the genus in the number of their vertebrae 

 and in the pattern of the molar teeth. The almost rudimentary 

 tail which remains concealed within the body has, however, four 

 more vertebra, ten in all, in the tree hyraxes. 



The animals of this group are really much modified 

 descendants of an extremely primitive and ancient type of 



two genera in this familj', Procavia and Dendrohyrax, the last-named for the 

 tree-dvvelHiig members of the group ; but there is scarcely a sufficient generic 

 distinction between them. 



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