BREED ING HAB ITS OF AMPHIBIA 



33 



HYLA VERSICOLOB , the tree frog. This small (2 to 2^ inches) arboreal species is partial 

 to woodlands and hushy areas but may be found far removed from moist areas, around build- 

 ings, walls, fences. It is found in eastern United States and Canada, The skin la moist 

 and slightly rough; the toes are webbed and their tips expanded into disks for adhering to 

 tree bark; the back may be uniformly colored or blotched, but is never stripped. There ia 

 a white spot under the eye and yellow and brown markings on the groin. These froga can 

 change their body color conaiderably. The male has the usual thumb pad and throat charac- 

 teristics. 



Breeding occurs in quiet ponds surrounded by high vegetation between the middle of 

 May and the middle of June when the air temperature ia at least 72°F. Egg-laying takea 

 about an hour, the paired animals depositing about 50 egga at a time until one or two 

 thousand are layed. The Jelly, which holds the entire egg mass together, is of loose con- 

 aiatency. The egga are brown at the animal pole and yellow or cream at the vegetal pole. 

 The eggs hatch in U to 5 days into larvae ■^■ inch in length. The tadpole reaches a length 

 of 2 inches and metamorphoses in ^5 to 6o days, never measuring more than 1 inch. The 

 newly metamorphosed froga are green and without characteristic markinga. The length of 

 life ia probably about 9 yeara. 



These forms are herbivoroua, living on minute algae and diatoms 

 in early life and later living on non-aquatic Insects. 



PSEUDACRIS NIGRITA. the awamp tree 



frog. This frog is found widely 

 except in New England) and the 



diatribut'ed over the United States 



males rarely exceed l-f inchea and the females 1^ inchea in length. 

 It haa three broad, dark atripes that extend down the back, and the 

 tips of the toea bear small disks. The akin of the chin and the 

 throat of the male is loose and dark. 



Breeding ia in any small body of water, permanent or temporary, 

 from the middle of March to the middle of April. About 500 to 1,500 

 eggs are layed in cluatera. Hatching occurs In about 2 weeks, and 

 larval life lasts from 1+0 to 90 days while the tadpole attains a 

 length of l-j- inches. 



Pseudacris nigrlta, 

 thie swamp tree frog. 



(Courtesy C. H. Pope 

 19l).l4-: Chicago Mus. 

 Nat. mat.) 



BANA CATESBIANA . the bullfrog. This large frog is found East of the Rockies from Mexico 

 to Canada, and is known to have a life span of 15 years. Its typical haunts are small 

 lakes and permanent ponds with much vegetation, generally shadowed by willows and other 

 low trees. 



The species can be recognized by the fully webbed hind feet, pointed toes, uniformly 

 dull green back (no warts or plicae) and the size of adults ranges from l*- to 8 inches, 

 from snout to anus. The males have a slightly larger tympanic membrane than do the females, 

 a pigmented thumb pad, and yellow throat. 



The male bullfrog, 

 Rana catesbiana. 



(Courteay C. H. Pope 191*-'+: 

 Chicago Mua. Nat. Hist.) 



Ovipositioii of Raiia cates- 

 belana; lateral view. 



(From Aronson 191+3: Am. Mus. Nov. #1224) 

 (Artist Mr. Eichmond E. Lawler) 



Its natural food in the larval stage ia diatoms and algae; as young frogs it is in- 

 sects and other small invertebrates; and as adults, any moving object, invertebrate or 

 vertebrate, that can be ingested. This includes fiah, frogs, salamanders, young turtles, 

 moles, mice, and even birds. In the laboratory the bullfrog may be fed smaller frogs. 



