The Swamp Tree Frog 



However, the chorus is loud enough, so that it is usually attributed 

 to some large frog (Rana.) The single call is a somewhat musical 

 rattle that lacks great carrying power. It is not shrill. (The 

 pitch varies with the individual between E above middle C and C 

 above.) There is a slight rise in pitch, an increase in emphasis, 

 and the crepitations are not especially rapid. ^ The call conveys 

 to the mind something of the idea of gentleness and comfort so 

 distinctly given by the trill of the Common Tree Frog. The call 

 is given by the male only; the inflated throat-pouch is large. 



The Swamp Tree Frog stays about the marshes throughout 

 the summer and fall. We may sometimes hear the isolated call 

 from marshy land during the hottest part of the summer, but on 

 the whole, the species is rather silent except during the breeding 

 season. These frogs seek refuge in the water when they are dis- 

 turbed, but are very poor swimmers, and soon come back to the 

 shore or crawl out on some miniature log. They are seldom seen 

 after the spring months, owing to their minute size, their protec- 

 tive colouration, and their silence. They feed upon flies, beetles, 

 and various insects that frequent marshy places. 



The Swamp Tree Frog is slender and delicate in appearance. 

 It has great power to change its colour between light and dark 

 shades. It has a colour pattern that not only is variable but has 

 the evanescent character common among the Hylidae. That is, 

 each tree frog has its own distinctive pattern of dress — we can 

 scarcely find two alike among several dozens caught in the same 

 locality — and in addition to this great variation, the given pat- 

 terns may be wholly absent at one time, faintly outlined at 

 another and prominently marked a third, all within the space of 

 an hour. 



The eggs are laid in shallow water m March or April. ^ They 

 are in small bunches of from five to twenty eggs, and are attached 

 to twigs and grasses in the water. Eggs laid March 22d hatched 

 April 5th. The tadpoles, both at their time of hatching and later, 

 are nearly black in colour. They can be distinguished from those 

 of the Leopard Frog, which hatch at about the same time, by 



iThe call is not so loud nor so sharp in quality as that of the Cricket Frog (Acris); the crepi- 

 tations are not so rapid. 



2 March 22, 18S8, Chorophilus Iriscrialus. March 20, 1892, Chorophilus jcriarutn. Irvington, 

 Ind. O. P. Hay. 



March 13 and 24, 1890; February. 23, 1S91. Chorophilus Iriseriattts, Baltimore, Md. T. H. 

 Morgan. 



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