-^ Fauna : Reptiles, Amphibians, and Fish 



perfectly collected and studied. The list of species, when the 

 country has been thoroughly investigated, ought to be a much 

 longer one than I am able to give (quoting from Dr. Biittikofer) 

 at the end of this chapter. There may yet be discovered 

 other species akin to the remarkable " hairy " frogs of the 

 northern Congo and Gaboon coast-lands, in which the flanks 

 and thighs are covered with a fringe of blackish filaments 

 (really excrescences of the skin) which resemble hair or bristles 

 in appearance. As it is, three true frogs [Rana and Rappia ') 

 have been recorded from Liberia, a toad (^Bufo regu/aris), and, 

 lastly, a representative of a very peculiar sub-order of Tongue- 

 less frogs, Xenop'us, a group which retains some archaic features 

 and yet has become much modified and specialised along a 

 line of its own. 



The Aglossa or Tongueless frogs are confined in their 

 distribution to Africa and northern South America, possibly 

 another result of the former Eocene bridge connecting the 

 two continents. The species which is found in Liberia — 

 Xenopus calcaratus — is a little creature only about two inches 

 long, which has very small eyes and a tiny tentacle projecting 

 below the eye (like that in the blind Coecilian). There is a 

 spur or claw of some length on the ankle. The toes are 

 armed with pointed nails, and are connected with broad webs. 

 The hind limbs are very large in these Xenopus frogs, which 

 lead a wholly aquatic life. The common form in West Africa 

 (X calcaratus — which has very small eyes) floats a good deal 

 on the surface of the water or hides under duckweed and 

 water-lily leaves. It is a type of amphibian that has reverted 

 to an entirely aquatic existence just as the whale has done 

 amongst mammals. These frogs have been observed by the 



' Rappia differs from the large genus of Rana by having fingers as well 

 as toes webbed and terminated with discs. 



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