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SNAKE FAUNA OF SOUTH AFRICA. 



The Palaeophidae, a fossil family of large marine snakes, is 

 known from the lower and middle Eocene of Europe and one 

 genus Pterosphenus occurs in the middle Eocene of Egypt and of 

 Alabama. 



It will be seen from the above that the Asiatic region (including 

 therewith the European) has representatives of every family and 

 sub-family of snakes with but one exception (the Rhachiodontinae, 

 comprising the single genus Dasypeltis); America ranks next in 

 importance, having much in common with the Asiatic fauna, but 

 lacking several families ; Africa is well represented, but is without 

 any members of about four important groups which are common to 

 the Asiatic and American regions ; Australia has a smaller number 

 of families, and Madagascar is still more poorly represented. The 

 groups common to all these regions are Typhlopidae, Boidae, 

 Colubrinae, and Dipsadomorphinae, and it is important to note 

 that the former two families are amongst the most primitive of 

 snakes, still retaining the character of the hind limbs, whilst the 

 Colubrinae is the least specialised group of the very large family 

 of Colubridae, and Dipsadomorphinae comprises snakes which are 

 not much modified from the primitive type. Now the Madagascar 

 Ophidian fauna consists simply of the above-mentioned four cos- 

 mopolitan groups of comparatively primitive snakes, and in addi- 

 tion but one odd species, constituting a peculiar genus, of the 

 aquatic Homalopsinae ; this latter snake belongs to a family which' 



