BATRACHIANS OF THE VICINITY OF NEW YORK 185 



folds of the operculum. This is in contrast with the larvae of 

 the salamanders, in which the operculum is absent and the fore 

 limbs are nearly full grown before the rear pair is visible. More- 

 over, the tadpoles of the salamanders retain their gill-stalks on 

 each side of the head until after the growth of the limbs is 

 completed. 



A popular key to the identification and classification of the 

 Toads and Frogs follows : 



Key to the Toads and Frogs. 



I. Tips of toes (digits) expanded in 



the form of adhesive disks or 



"suckers " The Tree Toads. 



a. Size very small. 



1 . Disks but slightly developed. 

 Brown; a wide green band on 



the back Cricket Frog (Acris gryllus crepitans). 



Gray ; three brown bands on 



the back Swamp Tree Toad {Chora philus triser- 



iatus) . 



2. Disks well developed. 



Brown to green (varying) ; a 



dark, X-shaped mark on the 



back Pickering's Tree Toad (Hyla pickeringi) . 



h. Size small. 



Bright green above, which hue 



is bordered on sides with a 



band of white. A purplish 



band from behind nostril. . . . Anderson's Tree Toad {Hyla andersoni). 

 Grayish, with wavy, irregular 



markings Gray Tree Toad {Hyla versicolor). 



II. No digital disks. Size moderate to 



large The Toads and Frogs. 



a. Size moderate. 



I . Skin thickly studded with wart- 

 like tubercles ; a large gland 



behind the eye The Toads. 



Pupil of eye horizontal Common Toad {Bujo lentiginosus amer- 



ica nus) . 



Pupil vertical Spade-foot Toad {Scaphiopus holbrooki). 



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