Hylidae 



Northern forms (triseriatus and sepientrionalis), frogs from the 

 South (nigritus) have a muzzle considerably drawn out, and those 

 from the East (feriarum) are distinguished by relative shortness 

 of the muzzle. Length of legs variable. In the southern and 

 eastern forms (nigritus and feriarum Baird) the length of the leg 

 to the heel equals or slightly exceeds the total length of head and 

 body. In forms at the extreme North (sepientrionalis), the legs 

 are unusually short, the length to the heel not equalling the length 

 of body forward to the ear. Those forms intermediate in distri- 

 bution (triseriatus) have a leg measurement between these two. 



Structure: Skin of upper parts finely tubercular; underparts 

 granular. The head is narrow and pointed. Nostrils much 

 nearer to the tip of the muzzle than to the eye. Muzzle extends 

 beyond the line of the jaw. Ear small, only one-fourth to one-half 

 the diameter of the eye. Eyes widely separated. Long slender 

 toes scarcely webbed. Disks on fingers and toes very small. Inner 

 and outer sole tubercles small; subarticular tubercles present. 



Range: This member of the Hylidae has the widest distribu- 

 tion of any member of its group in North America. It has been 

 reported from every state, with the exception of those of northern 

 New England, and Arizona, northern New York, Michigan, Cali- 

 fornia, Oregon, and Washington. In Canada it extends quite to 

 the Hudson Bay region. 



Pickering's Hyla is not the only tree frog that sings in ringing 

 choruses in early spring. In the Southern States the Swamp Tree 

 Frog (Fig. 185) is heard singing in late January and early February, 

 usually before Pickering's Hyla has begun peeping. The chorus 

 of the Swamp Tree Frog proceeds from ditches, marshes, and pools, 

 especially in low lands. These tree frogs are partial to temporary 

 pools which are wholly shut in from approach by tangled growths 

 of shrubs and woody vines. From such sheltered, sunny places 

 they sing throughout many of the days, and of course during the 

 night, until late April, when the breeding season is over. 



The chorus is not so penetrating as that of the Pickering's 

 Hyla, nor has it the ringing sleigh-bell character of the latter. It 

 is soft, relatively low-pitched, and is said to have a soothing 

 sound that swells and recedes " like the waves of the seashore." 



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