CLASS REPTILIA 561 



back and one on either side. Every portion of North America 

 is inhabited by a species or variety of this genus. The garter- 

 snakes are so difficult to classify that our description must be 

 only a general one. The species T. sirtalis possesses nineteen 

 rows of scales on the body, and- certain peculiarities in the 

 scales (shields) on the chin. The garter-snakes are the most 

 abundant of our harmless snakes. They are the first to appear 

 in the spring and the last to hibernate in the autumn. Their 

 food consists largely of frogs, toads, fishes, and earthworms. 

 The young are brought forth alive, usually in August, and 

 become mature in about one year. 



The common water-snake, Natrix fasciatus variety sipedon, 

 belongs to a genus whose species and varieties are abundant in 

 the United States, Europe, and Asia. They are semiaquatic 

 serpents, living in swampy places or in the vicinity of ponds and 

 streams. The water is usually selected by them as an avenue 

 of escape when disturbed. The variety sipedon of the eastern 

 United States is pale brownish or reddish in color, with wavy 

 cross bands of brown ; these break up into blotches on the hinder 

 part of the body. The length of an adult is usually about three 

 feet six inches. Like the garter-snake, the water-snake is vivip- 

 arous and about twenty- five young are produced in August 

 or September. The water-snake is often erroneously called 

 " water-moccasin." 



The black-snake, Zamenis constrictor, is a slender, long-tailed 

 snake of the eastern United States which reaches a length of six 

 feet. West of the Mississippi it gives way to a color variety 

 Z. constrictor variety flaviventris , called the " blue " racer. 

 In the East the black-snake is slaty black except the chin and 

 throat, which are milky white. In Michigan and adjoining states 

 it is bluish green above and immaculate white beneath. Con- 

 trary to popular belief, this reptile does not attack snakes larger 

 than itself, has no power to squeeze its prey to death, and is 

 unable to hypnotize birds and squirrels. Its prey is almost 

 always smaller than itself, and is swallowed while still alive, often 

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