366 Illinois State Lahoratory of Nafural History. 



Length of body. 2.62; tail, 2.31. 



Southern Illinois, abundant. Makanda, Cobden, Anna, 

 Saratoga, W. North field (Yarrow). 



The head and ventral side of the tail are as a rule almost 

 or quite devoid of spots. Young examples generally have the 

 spots as numerous on the top of the head as elsewhere. The 

 margins of the vent are pale in the darkest examples. Under 

 stones and logs in southern Illinois this salamander is very 

 abundant. It sometimes occurs in caves. I have never seen 

 it in the water. Once disclosed, it is easily captured, as its 

 movements are not rapid. It has been reported common 

 throughout the State, but occurs in laboratory collections made 

 in Union county only, though doubtless it is common in other 

 counties adjacent. 



Plethodon erythronotus, Green. Red-backed Salamander. 



Var. erythronota. 



Salamandra erythronota. Green, .lour. Acad. Nat. Sci. Phila., 

 1818, 1., p. 356.— Harlan, .rour. Acad. Nat. Sci. Phila., 1876, 

 v., p. 329.— Storer, T3ost. Jour. Nat. Hist., 1840, III., p. 53. 



PletJiodon erythronota, Baird, Jour. Acad. Nat. (Sci. Pnila., '2d 

 Ser., 1849. I., p. 285. 



Plethodon erythronotus, var erythronotus, Cope, Pros. Acad. 

 Nat. Sci. Phila., 1869, pp. 99, 100. 



Plethodon cinereus, subsp. erythronotus, Davis and Rice, Bull. 

 111. State Lab. Nat. Hist., 1., No. -5,1883, p. 12; Bull. Chicago 

 Acad. Sci., 1883. 



Var, cinerea. 



Salamandra cinerea, Green, Jour. Acad. Nat. Sci. Phila., 1818, [., 



p. 326.— Harlan, Jour. Acad. Nat. Sn., Phila., 1826, V., 



p. 330. 

 Plethodon (-inereits. Baird, Jour. Acad. Nat. Sci. Phila., 2d Ser., 



1849, I., p. 2S5. 

 Plethodon erythronotus, var. cinereus, Cope, Proc. Acad. Nat. 



Sci. Phila., 1869, p. 100. 

 Plethodon cinereus, subsp. cinereus, Davis and Rice, Bull. Ill 



State Lab. Nat. Hist., I., No. 5, 1883, p. 12; Bull. Chicago 



Acad. Sci., 1883. 

 Salamandra erythronota, De Kay, Nat. Hist. N. Y., I., Zoo). III., 



Rept. and Amph., 1842, p. 75, pi. 16, tig. 38. 



