a greenish brown with a bright green mask from the tympanum for- 

 ward along the jaw. The skin may be slightly roughened with small 

 tubercles. The legs have dusky bars. An occasional green frog has a 

 few scattered black spots on the back. They are white beneath, the 

 male having a yellow throat. 



Structure: A large frog; skin smooth; broad short fold of skin on 

 which is a yellowish white stripe extending from angle of mouth over 

 arm insertion; dorsolateral fold 1/2-2/3 distance to hind limb; fourth 

 toe free of webbing on last two phalanges; male with enlarged thumb 

 and tympanum; male with ring of yellow in tympanum; male with 

 throat a bright yellow; the swollen throat of the croaking male is a 

 flattened pouch not a ball-like sac; the vocal sacs being termed 

 internal. 



Voice: The call is low pitched, explosive. The note resembles that 

 made by plucking the string of a bass viol or the twang of a rubber 

 band slightly stretched over an open box. The male rests on a mat of 

 vegetation or amongst grass or aquatic plants, or freely sprawled out 

 on the water. Usually the hind quarters are slightly submerged. 



Breeding: In the north they breed from the end of May to mid- 

 August, but in the south they are late breeders. The black and white 

 eggs are in a surface film usually less than a foot square, and number 

 1,000-4,000. The egg is 1/16 inch (1.5 mm.), the inner envelope 

 elliptic, the outer merging into the jelly film. The olive green tadpole 

 is large, 2 9/16 inches (64 mm.), its tail elongate, green mottled with 

 brown, and with tip acute. The tooth ridges are 2/3, rarely 1/3. It 

 spends one winter as a tadpole and transforms from April to Septem- 

 ber at 7/8-1 1/2 inches (23-38 mm.). Many transform at smaller size 

 in the south. 



Notes: June 21, 1907. Slaughter House Pond, Forest Home, 

 Ithaca, N. Y. I found out in the middle at the surface, eggs laid by 

 six pairs. In one case the complement was distributed in four groups 

 about a foot apart. In other cases, they were generally in one mass. 

 They were readily distinguishable because of the excessive amount 

 of air bubbles amongst them. 



June 16, 1910, Ithaca, N. Y. East Bools. I heard Rana clamitans. 

 In the west stretch was one solid mat of water weed. On the top of 

 this at surface was a film 9 inches in diameter apparently fresh. A 

 little farther on were two other films, irregular crescents, one on open 

 water. ... In shallow water were two bunches two days old, one 

 other bunch a composite of two with a diameter 15 inches x 10 

 inches, another bunch in deep water, fresh but already distributed in 

 little packets. Along the west side were five fresh films, one 14 inches 

 x 9 inches, but looking like two, another bunch about hatched. 



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