THE BIOLOGY OF THE RED-BACKED SALAMANDER 

 (PLETHODON CINEREUS ERYTHRONOTUS 



GREEN). 



M. ETHEL COCHRAN. 



DISTRIBUTION. 



Baird says, "Species of the genus Plethodon are found all 

 across the North American continent." Boulenger makes the 

 range of the subfamily Plethodontinfe North America, with 

 possibly one species in the valley of the Rio de le Plata. Of 

 the subfamily Plethodontinse, Gadow states that it "is almost 

 entirely American (with one species, Spelerpes fnscus, in 

 Europe)," while Holmes says that "the Plethodontinse form a 

 large group which is mainly confined to America." In the 

 last edition of his "Manual," Jordan gives the range of the 

 family as "chiefly North America." 



The "red-backed" salamander (Plethodon cinereus erythronotus 

 Green) belongs to the Plethodontinae and according to Jordan 

 is confined to the eastern United States. Gadow says, "Ple- 

 thodon erythronotus extends into Canada," while Boulenger 

 would have it range in the eastern United States and Canada. 

 Cope claims the species Plethodon cinereus, including all varieties, 

 has an extreme range, being "found throughout the United 

 States, east of the Mississippi River. It appears to be more 

 abundant in the Middle States; its northern range is to the middle 

 of Maine, Ontario and Michigan." Kingsley says it is the "most 

 abundant salamander in the eastern United States." 



Throughout Worcester County, Mass., this little salamander 

 has proved very abundant. It is not an uncommon thing to 

 find twenty or more during a short afternoon's walk. Every 

 little wood has its dainty, shy, inhabitants who so easily may be 



overlooked. 



HABITAT. 



The tiny creatures are not visible to the casual observer, for 

 on bright days they are always concealed beneath stones or fallen 

 logs. Holmes says they are in damp situations under rocks or 



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