Liberia ^ 



poisonous and in which the poison-teeth are not immediately in 

 the front of the upper jaw, but are preceded by a considerable 

 number of small harmless teeth. The poison-teeth are some- 

 times three in number, and they are generally grooved for 

 the descent of the venom and not perforated. The Psammophis 

 and I'helotornis snakes also belong to this group of poisonous 

 colubrine snakes which have grooved teeth at the back of 

 the upper jaw and not in the front, like the cobras. 



The egg-eating snake (^Dasypeltis) and numerous harmless 

 (aglyphous) colubrine snakes (mostly tree-dwellers) are present 

 m Liberia. 



There are at least two species of burrowing snakes 

 (^Typhlops). These are at once the most degenerate and yet 

 generalised of snakes, descendants of an early branch of the 

 sub-order which have become specialised for life underground 

 and have nearly lost the functional use of their eyes. These 

 typhlopine snakes offer a remarkable external resemblance to 

 a large earth-worm, just as the enormous blue-green earth-worms 

 of Liberia i^Acanthridilus) do their best to look and act like 

 snakes. In Typhlops^ as in some other burrowing serpents, the 

 head looks so like the tail as to justify the name of " two- 

 headed " snakes by which Americo-Liberians know them. The 

 eyes are very minute and scarcely functional. The mouth is 

 small, and these snakes live on insects and small worms. 



The Python family is represented by two species — Calabaria 

 and 'Python. Calabaria is an inconspicuous snake of somewhat 

 dull coloration, about four feet long, with a relatively small 

 head. It is sometimes styled the West African boa, but it 

 is not nearer to the boas than to the other members of the 

 same group (£rv.v. Boa., Python., etc.). The name, therefore, is 

 somewhat misleading. There is a veritable boa in Madagascar, 

 a most remarkable fact in African zoography, because the 



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