SNAKE POISONS TREATMENT 117 



the blood, by a method that is practically instantaneous, and 

 very effective. First there must be a puncture, then the in- 

 jection of the poison. 



To pierce the skin and flesh, the rattlesnake has two 

 .special teeth, called fangs, which are very long, slender, 

 slightly curved, and exceedingly sharp at the point. A 

 slender tube traverses the axis of the fang, from the root 

 almost to the point, for the passage of the venom. Around 

 each fang is a flexible sheath of tough, white skin, evidently 

 for its protection. 



The fang of a diamond-backed rattlesnake the largest 

 species is about an inch in length. The small bone in which 

 it is set at the root (maxillary) is so hinged by tough ligaments 

 attaching to the roof of the mouth that it has some freedom 

 of motion. When the jaws are closed, the fangs lie against 

 the roof of the mouth. When the serpent strikes an enemy 

 with the intention of poisoning it, the mouth is opened widely, 

 the pterygoid bone pushes hard against the maxillary, and the 

 sheathed fangs are thrown forward until they look like great 

 hooks of white skin. 



A serpent cannot be rendered permanently harmless by 

 the removal of its fangs, because the fangs are constantly re- 

 newed. Each operating fang is backed up by a series of 

 smaller ones, of different sizes, growing and awaiting their 

 turn to do duty, and drop away. An adult fang is shed 

 every six or eight weeks. The old tooth does not drop out 

 until the new one is close beside it, duly connected with the 

 poison gland, and ready for duty. Then the old fang either 

 drops out, or is left sticking in the next animal bitten. 



