344 NATURAL HISTORY OF AFRICA. 



buries itself in the sand ; and when dropped from a 

 height, it immediately sinks beneath the surface of the 

 spot on which it fell. " These little creatures," says Cap- 

 tain Lyon, " are eagerly bought by the girls and married 

 women, for the purpose of ascertaining how many children 

 they shall have. By stretching them the skin will imme- 

 diately crack, and the women most religiously believe that 

 for every sound they shall bear a child." 



One of the most remarkable families of the saurian tribe 

 ^ is that which contains the chameleons. The common 

 species {Lacerta Africana) is found in Egypt, Barbary, and 

 the south of Spain. The changes of colour in these ani- 

 mals, though by some deemed fabulous, are now beyond 

 dispute. The causes of these changes, however, and their 

 mode of action, may still be classed among the more ob- 

 scure points of natural history. They seem independent 

 of external objects, and vary within a certain range, almost 

 every hour. 



" Non mihi tot ciiltus numero comprendere fas est • 

 Adjicit omaius proxima quaeque dies." 



3d, Ofhidian reptiles^ or serpents. Among the most re- 

 markable of the African species of this division, is the ce- 

 rastes, or homed viper. It is characterized by a small 

 curved horn over each eyelid. It lives in the sand, and 

 was well known to the ancients. Another singular ser- 

 pent is the haje {Coluber haje, Linnaeus). The Egyptian 

 jugglers, by pressing the neck of this creature between 

 their fingers, produce a kind of catalepsy which renders it 

 stiff and motionless. This is rather a curious fact when 

 • considered in connexion with the scriptural narrative in the 

 seventh chapter of Exodus, where the rods of the magicians 

 when thrown down are converted into serpents. 



This species was regarded by the ancient Egyptians as 

 the emblem of the protecting divinity of the world, and its 

 figure is frequently sculptured on each side of a globe, on 

 the outer gates of their temples. 



4th, The Batrachian reptiles, such as frogs, &c. Africa 

 produces comparatively few species of this division. The 

 soil is probably too dry. We shall here mention only 

 the short-headed toad {Rana breviceps) described by Lin- 



