THE TRUE FROGS 



(Ranidae) 



The true frogs are chiefly distinguished externally by their smooth 

 skins and by the fact that, though they may wander away from 

 the water, they usually prefer moist areas. 



Northern Wood Frog (Rana cantabrigcnsis) 



Appearance. This frog can be recognized immediately by the 

 dark brown, triangular mask which runs from the nostril back 

 across the eye and ends behind the ear. A white line runs along the 

 edge of the upper jaw, just below the mask. On each side a more 

 or less broken, dark brown line may run backward from the top 

 of the mask almost to the thigh. There may also be a pale line 

 along the length of the backbone. The ground color is brown 

 above, varying from an ashy fawn color through reddish brown 

 to a dark, leaf brown. The underside is yellowish white, occasion- 

 ally mottled with brown. 



The tadpole is grayish brown above, flecked with gold, and is 

 iridescent gray bronze beneath. The fin does not extend up on the 

 body. 



Size. Adult length 36-56 mm. 



Habitat. As its name implies, this frog lives in fairly dense, 

 rather damp woods. 



Breeding Habits. The eggs of this frog are laid some weeks be- 

 fore those of its relatives and consequently are sometimes frozen 

 in the ice and killed. If the water stays very cold, the eggs may not 

 hatch for weeks. If brought indoors the same eggs will hatch in 

 four days. Although the eggs laid in March may be lost, there is 

 usually another breeding period of the stragglers a few weeks later, 

 so that most pools in the woods, fields, or even wooded river bays 

 contain these frogs in the spring, as attested by the harsh, clacking 

 croaks of the males, a sound resembling the noise made by dragging 

 a shingle along a picket fence. 



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