OPHIDIA 241 



Snakes, while showing considerable intelligence, are seldom 

 much attached to their keepers, being more often reticent and 

 surly. 



Multiplication. — The eggs of snakes are not hard shelled, 

 but are covered with a tough membrane. Generally the snake 

 loosely buries the eggs or deposits them half-hidden in cracks 

 and crevices. Many snakes are ovoviviparous.' The young 

 are precocial. Male snakes are smaller than the females. 



As in reptiles generally, the number of young at a litter is 

 large, but the number varies with the species. That of the 

 poisonous snakes is said to seldom exceed fifteen, except those 

 of some of the tropical ones. Ditmars mentions a boa con- 

 strictor in captivity which " gave birth to sixty-four fully devel- 

 oped young, while a huge python deposited seventy-nine eggs, 

 which she gathered in her coils and guarded jealously" until 

 hatched. During this period of incubation the body tempera- 

 ture is raised. Our little garter snake has a litter of about 

 thirty-five, while that of the common water snake has been 

 known to number sixty. The copperhead has about eight or 

 nine young. 



The length of life may be said to be considerably shorter than 

 that of the chelonians and crocodilians, as growth is more 

 rapid. Adult snakes received in the Zoological Garden, New 

 York, says Ditmars, have been kept for ten years without show- 

 ing signs of age, and pythons even fifteen years. The snakes 

 of this latitude hibernate in caves and dens or in deep crevices 

 between the rocks. In the tropical regions some species esti- 

 vate in summer. 



Defense. — Besides their protective coloration, snakes are 

 further provided with several means of defense. Some are 

 protected from their enemies by a characteristic odor, while 

 others have the deadly poison fangs. Another, and by far the 

 most common means, is by noiseless flight. A few species 

 burrow or slip into holes to escape, while the boa constrictors 

 squeeze their enemies to death. Most snakes will not attack 

 man if unmolested, and they are generally as much frightened 

 as the person is. They charm birds, probably by paralyzing 

 them with fear, until they can creep up to and catch them. 



' See Glossary. 

 16 



