THE SNAKES. 505 



The tongue of the Snake is long, black, and deeply forked at its ex- 

 tremity, and when at rest is drawn into a sheath in the lower jaw. In 

 these days it is perhaps hardly necessary to state that the tongue is per- 

 fectly harmless, even in a poisonous serpent, and that the popular idea 

 of the " sting " is entirely erroneous. The snakes all seem to employ 

 the tongue largely as a feeler, and may be seen to touch gently with 

 the forked extremities the objects over which they are about to crawl 

 or which they desire to examine. The external organs of hearing are 

 absent. 



The vertebral column is most wonderfully formed, and is constructed 

 with a special view to the peculiar movements of the Serpent tribe. 

 Each vertebra is rather elongated, and is furnished at one end with a 

 ball and at the other with a corresponding socket, into which the ball of 

 the succeeding vertebra exactly fits, thus enabling the creature to writhe 

 and twine in all directions without danger of dislocating its spine. 



This ball-and-socket principle extends even to the ribs, which are 

 jointed to certain rounded projections of the vertebrse in a manner al- 

 most identical with the articulation of the vertebrae upon each other, 

 and, as they are moved by very powerful muscles, perform most im- 

 portant functions in the economy of the creature to which they be- 

 long. 



The bones of the jaws are very loosely constructed, their different 

 portions being separable, and giving way while the creature exerts its 

 wonderful powers of swallowing. The great python Snakes are well 

 known to swallow animals of great proportionate size, and any one 

 may witness the singular process by taking a common field Snake, 

 keeping it without food for a month or so, and then giving it a large 

 frog. As it seizes its prey, the idea of getting so stout an animal down 

 that slender neck and through those little jaws appears too absurd to be 

 entertained for a moment, and even the leg which it has grasped appears 

 to be several times too large to pass through the throat. But by slow 

 degrees the frog disappears, the mouth of the Snake gradually widening 

 until the bones separate from each other to some distance and are held 

 only by the ligaments, and the whole jaw becoming dislocated, until the 

 head and neck of the Snake look as if the skin had been stripped from 

 the reptile, spread thin and flat, and drawn like a glove over the frog. 



The Serpents, in common with other reptiles, have their bodies cov- 

 ered by a delicate epidermis, popularly called the skin, which lies over 

 the scales and is renewed at tolerably regular intervals. Toward the 

 time of changing its skin the Snake becomes dull and sluggish, the eyes 

 look white and blind, owing to the thickening of the epidermis that 

 covers them, and the bright colors become dim and ill-defined. Pres- 

 ently, however, the skin splits upon the back, mostly near the head, and 

 the Snake contrives to wriggle itself out of the whole integument, usual- 

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