The Peeper, Hyla pickeringii {Holbrook). 43 



period from egg-deposition to transformation, not merely the true 

 larval stage. 



THE TRANSFORMATION. 



Transformation usually begins as early as July 1, although the 

 average date of transformation is July 6. The range of transformation 

 is from June 12 to August 1. The first record for 1906 is July 17; for 



1907, July 5 ; for 1908, July 21 ; for 1909, July 21 . The earliest records 

 of transformation are June 26, 1901; June 21, 1904; and June 12, 1911. 

 In normal years the peeper tadpoles of the year have transformed 

 by July 25. The latest transformation we have found is August 1 , 1907. 



The curve of 92 specimens from 17 different collections gives a range 

 of 9 to 14 mm., an average of 1 1 mm., a mode of 11 mm. (Plate x. Fig. 2.) 



THE AUTUMNAL DISAPPEARANCE. 



In the autumn, about September 1, the peeper from the trees, bushes, 

 and woods, from hillsides and lowlands, breaks its summer silence. 

 In 1912 they began peeping August 26. Four-fifths of our fall records 

 come in the month of October, particularly in the middle and latter 

 part, the latest date before winter disappearance being November 26, 



1908. In every instance the maximum air-temperature reached 60 

 degrees or higher. 



