The Common Tree Frog 



notice at dusk the near voices 

 of the redwings or the more 

 remote one of the wood-thrush. 

 However this may be, it is certain 

 that they do hear the voices of 

 their companion tree frogs, and 

 that they feel the warmth of the 

 spring air and of the shallow 

 sun-warmed water. 



The eggs are attached in 

 small groups, and also singly, 

 to grasses or plant stems at the 

 surface of the water. They are 

 not easily found unless the grasses 

 are separated and examined 

 minutely. The eggs are very 

 light in colour, grey above, white 

 below. They hatch on the sec- 

 ond or third day, at a very early 

 stage in the development. The 

 tadpoles are then about one- 

 fourth inch long and of a light yellow colour. After the hatching, 

 the development proceeds very rapidly, so that in three weeks 

 from the date of egg-laying, the tadpoles' not only are fully formed, 

 but have the hind legs budded. They have much gold-colour in 

 the skin, and the widely separated eyes are flame-colour. The 

 whole surface of the tadpole shows a brilliant metallic sheen, and 

 sometimes the tail is almost red in colour. The brightly coloured 

 creatures are very timid indeed, and move with the rapidity of 

 young fishes. This rapid movement saves them many a time 

 from the clutches of a great diving-beetle or some other enemy. 

 In early July, near the end of the seventh week after the eggs are 

 laid, the tadpoles complete the metamorphosis and leave the 

 water. It seems that the green dress is the one in which the 

 young frogs begin their life on land, but they may very soon change 

 to gre}^ or some combination of the two colours. When they are 

 green in colour, they can be recognized by the white spot under the 



When Jack-in-the-pulpit appears 

 ■we may expect to hear the trilling of 

 Hyla versicolour from pond and 

 river margins. 



1 The mouth structure of the tadpole of Hyla versicolor is as follows: The upper lip bears one 

 row of teeth, the lower has three. The upper lip curves downward at each side of the beak. The 

 border of the lower lip is not doubled in at the comers of the mouth. 



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