A AMPHIBUNS 



Green frog, Rana clamitans.— The green frog's head and 

 shoulders are bright green, shading to olive or brown at the 

 end of the body (PI. XXI). It has a lateral skin fold or ridge 

 on each side of its back, the under parts are white with indis- 

 tinct dark marblings; in the male the throat is washed with 

 yellow. Green frogs might be confused with small bullfrogs 

 except for the lateral folds which are never present in bull- 

 frogs (PL XXI and Fig. 309). 



Habits, habitat. -^Green frogs and bullfrogs live together in 

 swamps and ponds, but the green frog forages along small 

 streams not often frequented by the bullfrog. Green frogs 

 are solitary, only one or two staying in one pool, or in the 

 bends of the stream bank. 



They hibernate in the mud of ponds, often staying in 

 springs, wedged between stones or sprawled on the bottom 

 but swimming up into the open water on warm days. A 

 certain covered spring near South Hadley, Massachusetts, is 

 a regular winter resort for green frogs. 



Breeding habits. —Green frogs swim about through the 

 ponds very early but they do not begin their low-pitched 

 croaking until much later, and do not mate until the last of 

 May. From then until August they mate and lay their eggs, 

 almost always by night. 



Life history.— During June and early July the eggs are 

 very common and the egg masses are spread out like a film 

 nearly a foot across, over beds of Char a or other submerged 

 water plants or in the shallow water near shore where they are 

 destroyed in great numbers by drying. The water is usually 

 warm and the eggs often hatch into tadpoles in less than a 

 week. 



Green frog tadpoles which hatch in June do not transform 

 to frogs until the following spring or early summer. 



Size.—Body of the female 5 inches long, the male is smaller. 



Range.—Common in eastern and central United States and 

 southern Canada. 



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