DISTRIBUTION OF OPHIDIANS. 
215 
graphic distribution of serpents in that quarter of the 
world, and still less to assign to each species the precise 
limits which determine the habitats which Nature has 
assigned to each; not knowing in an exact manner, so 
to speak, more than the productions of the three or four 
principal points^ of this continent which have been explored, 
we find ourselves constrained to limit our indications of 
species, and of the places where they have been observed. 
Africa is, in general, much less rich in reptiles, and notably 
in serpents, than Asia and America. The number of 
genera is equally circumscribed in that continent ; but 
we find among reptiles the same phenomena which are 
observed in the other animals and plants of that part of 
the world ; namely, that the species of certain genera are 
extremely numerous, and that these different species often 
inhabit the same places : a fact which applies also, though 
less extensively, to New Holland. These are, in general, 
animals inhabiting plains, the number of species of which 
is multiplied in Africa. It is thus we see at the southern 
extremity of that continent three or four species of Land 
Tortoise, four species of serpents of the genus Coronella, 
as many of the genus Naja, and three of the genus Vipera. 
The other genera of serpents there produced, have only 
a single species to represent them. These snakes, almost 
without exception, pertain to species peculiar to that con- 
tinent. Some are found on the coast of Guinea ; such as 
the Lycodon of Horstock, and the Naja rhombeata ; the 
Psammophis moniliger is also found there ; but it forms a 
local variety approaching to that inhabiting Egypt. In Se- 
negambia, three species of Tree- Snakes of the genus Ben- 
drophis are found, different from those of the Cape, one 
of which, B. picta, is spread over a great part of Asia, 
even to New Guinea. The intertropical regions of Africa 
support the Two-rayed Python, the native country of which 
extends even to China, and the Island of Java. The 
Lancing Viper of the Cape, Vipera arietans, is also found 
in Abyssinia, where it forms a local variety with pale 
* Egypt as far as Abyssinia, Algeria, one part of Senegambia, and of 
the coast of Guinea, the Cape Good Hope. 
