FROGS. 17 



The green frog is one of the sohtary species. In habitat itis not 

 as restricted as the bullfrog. Both occur in swamps, and in our 

 deeper, larger ponds and reservoirs. In the smaller ponds and pools 

 only the green frog is present. In fact, along watercourses there is 

 hardly a small pond (PL VI, fig. 1) which can not claima green 

 frog. In the swamps only does the leopard frog exceed it in abun- 

 dance. The latter often inhabits the less permanent situations; the 

 green frog usually chooses more permanent, deeper bodies of water. 

 The green frog starts to appear when the air reaches 54 to 61° and 

 quite commonly at 61 to 69°. It also, like the leopard frog, pickerel 

 frog, and bullfrog, hibernates in the water and awakens when the 

 temperature of the water reaches 46 to 58°. It most assuredly is 

 not "the first species heard in the spring." In fact, it does not 

 begin to croak until a month after its first appearance. Then its 

 low-pitched, short "bass-viol" note is very distinctive. The male 

 of the green frog also has enlarged thumbs, and, in addition, has a 

 yellow throat and a tympanum larger than the eye, while the female 

 has a tympanum only equal in size to the eye. This species, being 

 solitary, would be hard to secure alive in sufficient quantities for 

 breeding purposes unless more effort were expended on its capture 

 than it was actually worth. Wherever they are common, as in big 

 mill ponds and small lakes, one might take enough to determine if 

 the green frog be the species most desired. They are best taken at 

 night. 



Finally, in the East, the bullfrog appears to be the most desirable 

 because of its size. One commonly associates the bullfrog with 

 marshy bayous, buttonbush swamps, miU ponds (PI. VI., fig. 2), or 

 lakes. They are not, however, as restricted in habitat as some 

 texts might lead the reader to infer. The author has found them 

 along both upland and lowland streams, in clear brooks which fed 

 cold, marly, sphagnum ponds, and along watercourses laden with 

 such marshy vegetation as lizard's-tail, marsh cress, arrowhead, 

 pickerel weed, and swamp loosestrife. Rarely they have appeared 

 m small numbers in temporary or very smaU ponds, a more logical 

 home for the green frog.- Such distribution can ordinarily be ex- 



glained by the loss or draining of a former mill pond or reservoir 

 abitat near by, and such records are more accidental than normal. 

 These frogs seem to prefer mill ponds, hydraulic lakes, reservoirs, 

 and kindred bodies of water. The author's best collecting grounds 

 were a clear, glacial lake in a New England kettle hole, with a slight 

 suggestion of the sphagnous flora about it; a pond in a clear trout 

 brook; a large reservoir for a hydraulic laboratory; a disused mill 

 pond; and a wooded lake whose shifting water level had made a 

 iringe of overhanging dead trees, floating logs, and submerged roots 

 and limbs. In every case the shores were more or less wooded, but 

 more important are two factors: Shallows where the species can 

 transform; and brush, stumps whose roots are at the edge of the 

 pond or overturned and driftwood along the banks. 



When the buUfrog comes out, at least seven of the species which 

 appear in the spring are entirely or almost finished with their spawn- 

 ing. The bullfrog is such a wary form that in some years its presence 

 is not suspected until June, when croaking begins. When the air 



