CHAPTER XXXI 



THE GREEN FROG 



Cardanus undertakes to give reason for the raining of Frogs ; but if it were 

 in my power, it should rain nothing but Water Frogs, for those, I think, are not 

 venomous. — Izaak Walton, The Compleat Angler 



Habitat and Distribution. The green frog (Ra'na clam'- 

 itans, Fig. 172) is one of the commonest species of frogs in 

 the eastern United States. It frequents the neighborhood 

 of springs and meadow brooks and may be distinguished 

 from its larger relative, the bullfrog {Rana catesbia' no) , by 

 the presence of two glandular folds of skin along the sides 

 of the back. 



In many regions the most abundant frog is a smaller 

 species commonly called the leopard frog {Rana pip'iens). 

 The following descriptions of structure agree equally well 

 for bullfrog or leopard frog, though the green frog is the 

 species actually described. 



External Structure. The body is divisible into a head and 

 trunk ; there is no visible tail. The body covering is a soft, 

 smooth skin without scales, abundantly supplied with mu- 

 cous glands. There are two pairs of appendages, — the limbs : 

 the anterior of which are divisible into upper arm, forearm, 

 and hand ; the posterior, into thigh, lower leg, and foot. The 

 hand ends in four short fingers ; the foot, in five toes, joined 

 by a web. Both fingers and toes are often spoken of as 

 digits. The eyes are situated prominently on the top of 

 the head, and possess, in addition to an upper eyelid, a 

 thin fold of skin called the nictitating membrane, which can 



be drawn across the eyeball from below. There is no true 



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