' ENEMIES. 27 



introduced snakes into their cages. If the cage happened to 

 be rather small, the animal would show much alarm, but when 

 given a large roomy cage in which to operate, no fear was shown. 



In the "Cambridge Natural History" volume on Reptiles, it 

 is stated that " several well-known mammals and birds are im- 

 mune by nature against snake venom, but most of them avoid 

 being bitten. Some birds induce the snake to strike and bite 

 frequently into their spread-out wings. Such more or less 

 common creatures are the Mungoose, Hedgehog, Pig, Secretary 

 Bird, Honey Buzzard, Stork, and probably other snake-eaters." 



None of these creatures are immune to snake venom. If 

 the venom is injected under their skins artificially, or naturally 

 by a snake, they die. The hedgghog, owing to its spine-covered 

 body, is not likely to be bitten when attacking a snake. Pigs 

 are not actually immune. If a snake should drive its fangs into 

 the thick layer of fat under the skin of a pig, there is httle 

 probabihty of its being absorbed, except at such an exceedingly 

 slow rate that the animal suffers little or no inconvenience. 

 Pigs, which are allowed to range in a semi- wild condition under 

 natural conditions, develop a tough leathery hide, which the 

 fangs of snakes cannot easily penetrate. I have found that if 

 snake venom is injected into the tissues of a pig, among the 

 capillary blood vessels and lymphatics, the venom is absorbed 

 and produces characteristic symptoms of snake venom poison- 

 ing, as in other animals. The Secretary Bird, when attacking 

 a snake, defends itself with its spread-out wings, which it holds 

 in front of it hke a shield. The instant the snake lunges at the 

 quills, the bird throws the wings violently forward, casting the 

 snake backwards with great violence. If the reptile should 

 appear to be dazed, the bird at once seizes it by the neck in its 

 powerful bill, and, with a severe nip, crushes the backbone, and 

 thus incapacitates the snake. These birds often use their long 

 stilt-like legs like arms, beating the snake to death with a quick 

 succession of blows. The feet and legs of the Secretary Bird, as 

 far up as the knee joint, are hard, brittle, horny, and well-nigh 

 impervious to the fangs of a snake. 



Snake-eaters all owe their comparative immunity to death 

 from snake-bite to their agihty, methods of attack, and natural 

 defensive coverings. 



