REPTILES OPHIDIANS DIAGKAM 5. 91 



every year. The epidermis loosens in a single piece, first round 

 the lips, and then the animal moves backwards and forwards 

 among the stones, to shuffle off this epidermis along the whole 

 length of its body, till it finally comes out of its old skin like a 

 glove. 



Serpents feed only on living prey, which they swallow without 

 tearing or bruising them. A viper swallows a mouse or a small 

 rat at a single mouthful, in the following manner. It springs 

 on it, kills it, and seizes it by the head. The jaws of the 

 serpent are then seen to distend enormously, and by little and 

 little it swallows a prey larger than its own body. After it has 

 swallowed it, it lies motionless for a time, as if fatigued by the 

 exertions which it has made, whilst its head returns to its usual 

 size. 



There is in America a very large kind of serpent, the Boa, 

 which can swallow a sheep in this manner after crushing it in 

 the coils of its body, or against the trunk of a tree. The boa is 

 not venomous. 



There are, however, many other kinds of serpents which are 

 much more venomous than the viper the cobra or spectacle snake, 

 and the rattlesnake, are examples. 



The Spectacle SnaJce inhabits India. It owes its name to a 

 pattern on its neck which almost exactly resembles one of those 

 pairs of spectacles which were formerly worn, like eye-glasses, on 

 the nose. These serpents have the power of inflating their neck 

 with air, which gives them a peculiar appearance. They raise 

 themselves on their tail when they are irritated, and in some 

 countries the jugglers exhibit them in public, but they take care 

 beforehand to remove their fangs by giving them a piece of cloth to 

 bite, which they jerk sharply when the animal has buried its teeth 

 in it. After this, they are no longer dangerous, or at least their 

 bite is no more to be feared than that of the common snake. 



Rattlesnakes inhabit America, and are amongst the most 

 venomous known. They have a row of hard horny pieces at the 

 end of the tail, which make a noise when rapidly shaken ; and 



