THE BIOLOGY OF THE RED-BACKED SALAMANDER. 



335 



gently-inclined path to a mass of rocks about a foot below ground 

 where there were natural openings in all directions. The hole 

 then appeared to be nothing but a natural opening worn smooth 

 by use. Five other places were carefully studied where natural 

 crevices seemed to be utilized. 



The number of salamanders found under one object is variable; 

 the most ever found was ten and countless times has only 

 one been seen. There seems to be no evidence of their being or 

 living in pairs during fall and early spring. 



DESCRIPTION. 



Kingsley calls these salamanders "the smallest in the United 

 States." The largest specimen found measured 9.2 cm., while 

 from 7.8 cm. seems to be the average length. The tail is about 



Red-backs. (Natural size.) (Photographed by the author.) 



as long as the entire animal. Of two individuals, one, whose 

 total length was 9.2 cm., had a tail 4.9 cm. long, while one 7.8 

 cm. long, had a tail 4.2 cm. in length. Jordan gives their total 

 length as 3^2 inches (9 cm.). The following measurements 

 give some idea of the relative length and width of the body: 

 total length, 8.4 cm., tail 3 cm., costals 2 cm., width of head 

 5 mm., width of body 4 mm., dorso-lateral diameter 2 mm. 



They are slender, with an almost cylindric body and a sharply 

 pointed cylindrical tail. The legs are thin and weak and the 



