Fig. 35. Dried crystals of rattlesnake poison. It is dehydrated after extraction from 

 the snake to prevent decomposition. When used for immunization in producing 

 antivenomous serum, it is quickly soluble in distilled water. It retains its potency 

 for years in a dried state. (Right) Fangs of Rattlesnake, Fer-de-lance and Bush- 

 master, with horsehair passed through the orifice which extends from tip to the base, 



to show the resemblance to the hypodermic needle of the surgeon. 



Fig. 36. (Lower) Skulls of harmless and poisonous serpents. The latter shows reserve 



fangs and a double fang on right — one of these about to be shed. 



