THE SNAKES 245 



these intergradations and a fairly constant scale formula, 

 freak phases of coloration are unworthy of varietal 

 names. All of the "subspecies" and phases of Eutcenia 

 elegans have the lateral stripe on the second and third 

 rows of scales. 



The Common Garter Snake, E. sirtalis, may be 

 termed the most abundant of North American serpents, 

 occurring in every part of the continent where snakes 

 are to be found. Several varieties are recognized. 

 Among the western subspecies are several looking like 

 phases of Eutcenia elegans. Technically, they are to be 

 separated by the lesser number of scale rows. A simple 

 and good way to distinguish western examples of Eutce- 

 nia sirtalis from specimens of E. elegans is to examine 

 the two large pairs of chin shields. With E. sirtalis the 

 rear pair of chin shields is considerably longer than the 

 front pair ; E. elegans has both pairs of much the same 

 size. 



East of the Mississippi, the Garter Snake is every- 

 where the commonest serpent, stubbornly defying extinc- 

 tion even in the large city parks. The typical form itself 

 evinces a puzzling degree of variation in pattern and 

 in color. The commoner phase is dark brown above 

 with three yellowish stripes, the lateral ones on the sec- 

 ond and third rows of scales; between the stripes are 

 two well-defined rows of alternating spots ; beneath, the 

 color is greenish, or yellow. The skin along the sides, 

 when distended, shows numerous lineate spots of white 

 or green — but this is a general character among the 

 striped snakes. Specimens from mountainous districts 

 are frequently blackish, without stripes or spots. One 

 distinct variety — ordinatus — is strongly spotted, but 

 lacks traces of stripes ; it is found from Maine to Florida 

 and westward to the Mississippi. 



