GREEN OR SPRING FROG. 711 



in some cases, at least, in springs. They prefer thick oak or maple 

 forests as a habitation, and in Maine their notes may be heard as early 

 as April, but in our limits earlier. They are never found in the south- 

 ern states. Their color is quite variable being darker in spring, but be- 

 coming paler after exposure for sometime to light. The young are eight 

 lines in length immediately after the loss of their tail. 



An interesting fact meets us by comparison of the specimens of i2ana tem- 

 poraria of the Old World with those of the New. That it is exceedingly 

 variable is evident from the different varieties often mistaken for differ- 

 ent species in this country and on the eastern continent. The most note- 

 worthy fact, however, is that those of Japan and eastern Asia, in the size 

 of the tympanum and coloration, are intermediate between those of 

 Europe and our American varieties. 



Some at least of the other Amphibia show the same relations, thus indi- 

 cating, as pointed out by Prof. Marsh in regard to the extinct vertebrata, 

 that there had probably once, if not oftener, been an interchange of 

 faunas between the two continents through the region of Behring's 

 Straits. 



Rana clamitans Daudin. 



Oreen or Spring Frog:. 



Bcma elamata, Daudin, Dumertl and Bibron, Gunthbr 



Bana elamata, et flaviviridis, Harlan. 



Bana clamitans, Mkerem, Holbkook, AiiKN, Vekkill, Cope, Jordan. 



Bana fontinalia, LeConte, Stoker, 



Bana clamitans, fontinalia, et horiconensis, DeKay. 



t Bana nigreseens, Agassiz. 



Color above green to brown, -without any large spots ; legs and sides irregularly- 

 spotted or speckled -vrith darker ; beneath silvery -w-hite to yellow ; gnlar region often 

 irregularly spotted with darker ; thighs granulated posteriorly ; femur nearly as long as 

 tibia ; toes and fingers with small tubercles at most of the joints ; ! ympanum of medium 

 size or large, usually about eight or ten millimeters in diameter, but sometimes not 

 over four, its color green, with a central nucleus of lighter green ; eyes black ; irides 

 yellow ; muzzle rounded somewhat ; nostrils latero- vertical, half way between the eye 

 and snout; inner nares medium, slightly more widely separated than the outer; 

 vomerine teeth small, in two patches ; dorso-lateral cutaneous fold well marked, reach- 

 ing from the eye backwards. Length, 3 inches ; head to axilla. If inches ; hind leg, 4 

 inches ; fore leg, H inches ; transverse diameter of head, IJ inches ; vertical diameter 

 of head, 7^1 lines; transverse diameter of body, H inches. 



Habitat, Nova Scotia, Maine, Massachusetts, New York, Pennsylvania, North 

 Caroliua, South Carolina, Georgia, Ohio, Michigan, Illinois, Arkansas. 



The Green Prog is common along brooks and around ponds, sitting 

 upon the banks, and plunging at the approach of danger. In wet weather 



