BATRACHIANS OF THE VICINITY OF NEW YORK 185 
_ folds of the operculum. This is in contrast with the larve 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 
MRE TONE 0 Boa, sn ce ae sues goapens The Tree Toads. 
a. SIZE VERY SMALL. 
1. Disks but slightly developed. 
Brown; a wide green band on 
Dmermack...-.-............. Cricket Frog (Acris gryllus crepitans). 
Gray; three brown bands on 
Ue [O2IC2S Seager er ara Swamp Tree Toad (Chorophilus triser- 
zatus). 
2. Disks well developed. 
Brown to green (varying); a 
dark, X-shaped mark on the 
aM oc ge gi ts wheats wh Pickering’s Tree Toad (Hyla pickeringt). 
b. 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 andersont). 
Grayish, with wavy, irregular 
PMEMOS. . 0... sd. ses eee ees Gray Tree Toad (Hyla versicolor). 
II. No digital disks. Size moderate to 
J°T?.. 0 eee The Toads and Frogs. 
a, SIZE MODERATE. 
1. Skin thickly studded with wart- 
like tubercles; a large gland 
inehind the eye.......:..... The Toads. 
Pupil of eye horizontal........ Common Toad (Bujo lentiginosus amer- 
icanus). 
eeilevertical 0. 2. sce. wate nen Spade-foot Toad (Scaphiopus holbrookt). 
