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NATURE-STUDY REVIEW [11:5— May, 1915 



hinged plastron. We have also other turtles that can do this, but 

 they are not marked like our box tortoise, and can not be easily 

 confovmded with it. 



In the eastern United States we have two species of spotted 

 frogs that are frequently confused by young naturalists. One is 

 the Salt-marsh Frog {Rana virescens), here shown in Figure 4, and 

 the other is the Leopard or Pickerel Frog {Rana palustris). One 

 way to recognize the latter species is the regular arrangement 



Fig. 4. Salt-marsh Frog {Rana virescens). 



of the spotting on the back and sides, while in the Salt-marsh 

 Frog the spots are paler and irregularly disposed. The prominent 

 lines down the sides are simply raised, vein-like folds of skin, the 

 purpose of which, beyond being ornamental, is not known. You 

 will also meet with other kinds of frogs in the ponds of the Atlantic 

 States, namely the Pond or Green Frog {Rana clamata), and the 

 much larger Bull Frog {Rana catesbiana). The first named may 

 be easily distinguished from the former by the conspicuous, raised 

 skin-fold, beginning behind either eye and running down the side 

 of the body. This anatomical character is not found in the Bull 

 Frog. 



