506 THE KATTLESNAKE. 



Iv turuing it inside out in the process. This shed skin is transparent, 

 having the shape of each scale impressed upon it, being fine and delicate 

 a.s goldbeater's skin, and being applicable to many of the same uses, 

 such as shielding a small wound from the external air. 



The first sub-order of Snakes consists of those serpents which are 

 cla-ssed under the name of Viperina. 



All these reptiles are devoid of teeth in the upper jaw, except two 

 Jong poison-bearing fangs, set one at each side and near the muzzle. 

 The lower jaw is well furnished with teeth, and both jaws are feeble. 

 The scales of the abdomen are bold, broad, and arranged like overlap- 

 ping bands. The head is large fti proportion to the neck, and very 

 wide behind, so that the head of these Snakes has been well compared 

 to an ace of spades. The hinder limbs are not seen. 



In the first family of the Viperine Snakes, called the CROTALiDiE, 

 the face is marked with a large pit or depression on each side, be- 

 tween the eye and the nostril. The celebrated and dreaded Rattle- 

 snake belongs to this family. 



This reptile is a native of North America, and is remarkable for 

 the singular termination to the tail from which it derives its popular 

 name. 



At the extremity of the tail are a number of curious loose horny struc- 

 tures, formed of the same substance as the scales, and varying greatly 

 in number according to the size of the individual. It is now generally 

 considered that the number of joints on the " rattle " is an indication 

 of the reptile's age, a fresh joint being gained each year immediately 

 after it changes its skin and before it goes into winter-quarters. 



The joints of this remarkable apparatus are arranged in a very 

 curious manner, each being of a somewhat pyramidal shape, but 

 rounded at the edges, and being slipped withi'n its predecessor as 

 far as a protuberant ring which runs round the edge. In fact, a 

 very good idea of the structure of the rattle may be formed by slip- 

 l)ing a number of thimbles loosely into each other. The last joint is 

 smaller than the rest, and rounded. As was lately mentioned, the 

 number of these joints is variable, but the average number is from five 

 or six to fourteen or fifteen. There are occasional specimens found that 

 possess more than twenty joints in the rattle, but such examples are very 

 rare. 



When in repose the Rattlesnake usually lies coiled in some suitable 

 spot, with its head lying flat, and the tip of its tail elevated in the mid- 

 dle of the coil. Should it be irritated by a passenger, or feel annoyed 

 or alarmed, it instantly communicates a quivering movement to the tail, 

 which causes the joints of the rattle to shake against each other with a 

 peculiar skirring rufile very much like the sound of the escaping steam 

 ot a railway engine. 



