Pti,i, b) H. G. F. Sfurnll, Esy.\ 



DARK GREEN SNAKE 



A native of Italy and other countries bordering the Mediterranean. Accredited -with a particularly fierce disfositioa 



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CHAPTER V 



SNAKES 



THE characteristic contour of a snake's body is too familiar to need elaborate description ; 

 its leading features are, in fact, so nearly approximated by certain of the legless lizards, 

 previously described, that the distinctions between the two can with difficulty be defined. 

 Many of the snake-like lizards, including the Common Blind-worm, are altogether devoid of 

 external limbs. In some snakes, on the other hand, and notably the large terrestrial Pythons, 

 a spur-like development on each side of the base of the tail represents rudimentary hind legs. 

 The Snakes agree essentially with the Lizards in the character of their scaly covering, the 

 scales, however, being larger on their under-surface and specially adapted, as in the legless 

 lizards, for creeping locomotion. The essential distinctions between the two groups have to 

 be sought in the structure of the head. The most notable of these, as it obtains in the 

 Snakes, is the very loose manner in which all the bones connected with the jaws are held 

 together, thus providing for the greatest possible distension in the act of their swallowing 

 their prey whole, as is the custom of all ordinary snakes. To achieve this end, the two halves 

 of the lower jaw are not united together at their extremity or chin, as in lizards, but are 

 merely connected with one another by an elastic ligament. In most snakes the bones of 

 the upper jaw and palate are also attached to one another in a similar way. 



The eyes of a snake differ in a very marked manner from those of ordinary lizards. 

 No snake possesses movable eyelids. The eye, in compensation, is protected by a transparent 

 horny disk, continuous with the general epidermis, and is shed with it when the snake casts 

 its skin. This feature imparts to snakes that fixed, stony expression of the eyes which 

 undoubtedly contributes very materially towards increasing the feeling of repulsion with which 

 snakes are commonly regarded. A few exceptional lizards, such as the Geckos, have a similar 

 eye-construction, but it is not met with in any of the limbless or snake-like forms. No 

 snakes, again, show any trace of external ear-openings, such structures, on the other hand, 

 being distinctly developed in almost all lizards. The head itself of the snake is never 

 compressed or elevated, as in most lizards, but flattened down and usually wider than the 

 body, to which, however, it is united without a distinct neck. The tongue of the snake is 

 slender, and terminates in two long, thread-like points; basally it is inserted into a hollow 

 sheath, into or out of which the entire organ can be retracted or exserted at will. The 

 somewhat uncanny, flickering action with which a snake, while moving, displays and as it 

 were feels its way with its long, forked tongue represents another element which adds to the 

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