96 Practical Zoology. 



freshly killed snake sink or float ? Do snakes dive ? How do snakes 

 strike, when capturing prey or in self-defense? How far can a 

 snake strike? Let it strike some object, for example a stretched 

 paper, to show with what force it strikes. Do you know of any 

 case where a snake, unmolested, pursued a human being? 



LABORATORY STUDY OF A LIVE SNAKE. 



A snake may be kept in a large glass jar, but it is better to have 

 a shallow box, with glass lid. Test the snake's vision. Does it 

 see well? Does it see small objects as readily as large ones? 

 Does it notice slow motions as well as quick ones? Test its sense 

 of hearing. Try music. Does the snake protrude the tongue ? If 

 so, for what purpose ? 



Induce the snake to strike ; study the position and mode of 

 striking. Study the process of respiration in the snake. Is there 

 a pause ? What movement is first after the pause ? Compare the 

 snake's respiration with your own. Does a snake need much or 

 little oxygen as compared with man ? 



How soon does a snake become hungry after a meal? Offer 

 various articles of food. Does a snake drink? Offer it water in 

 a shallow dish from time to time. Will a snake eat a dead animal? 

 Do snakes of different kinds in the same box offer to molest each 

 other? Do snakes ever eat snakes of any kind? Do snakes sleep? 

 At what times are they most active ? When least so ? Watch a snake 

 to see the shedding of the skin. At what point does the skin begin 

 to loosen ? How is the skin peeled off? What is the condition of 

 the snake before shedding ? What is the appearance and condition 

 after shedding? How often does a snake shed its skin? 



EXTERNAL FEATURES OF A SNAKE. 



Examine the scales ; observe their relation to each other and to 

 the skin. A scale having a ridge running lengthwise in the middle 

 line is carinated ; if there be no such ridge, the scale is called 

 smooth. How many rows of scales are there, not counting the 



