VARIATIONS OF GARTER-SNAKES. 



177 



keels). The spots are not usually distinct upon the scales, however, 

 owing to the darkness of the ground color. Interspaces on the skin 

 white or bluish white, never red except occasionally immediately 

 along the lateral stripe. Stripes greenish or bluish, usually tinged 

 with yellow. Ventral surface greenish or bluish slate. Ventral spots 

 usually well defined. Sides of head greenish, yellowish, or bluish; 

 abials partly margined with black. 



Habits and liabitat relations.- — Even in the case of this well-known 

 form but little has been recorded on the habitat relations. The expe- 



FiG. 77 .—Forests ix the Porcupine Mountains, Michigan. Thamxophis sirtalis is of 



GENERAL distribution IN SUCH FORESTED REGIONS IN EASTERN UNITED STATES. 



rience of the writer indicates that it is quite generally distributed 

 in the Eastern forest region, for while it is found most commonly in 

 the vicinity of water, it is not uncommon in the clearings, woods, 

 and thickets on the neighboring hills (fig. 77). 



The food consists principally of frogs, toads, salamanders, earth- 

 worms, and various insects. Whether or not it feeds to any great 

 extent upon tadpoles and fish is undetermined. Garman (1892, 268) 

 states that they eat these animals, and I have observed them to 



