192 



BERTRAM G. SMITH. 



small tail rudiment. The latest embryos were collected on July 

 5; at this time nearly all the embryos had hatched, only a few 

 unhatched embryos being found in each of several nests. The 

 empty capsules remained attached by their stalks. 



Eycleshymer ('06) states: "The time of egg-laying varies in 

 different lakes, depending upon the time when the temperature 



FIG. i. "Nest" of eggs of Necturns. The stone to which the eggs are attached 

 has been removed from the water and set on edge on the wharf; it is about 16 inches 

 in diameter. The embryos are in an advanced stage of development. 



of the water reaches a certain degree. In the larger, deeper 

 lakes with bold shores this is much later than in those possessing 

 wide shoals. . . . According to Professor Whitman's and my 

 own experience the best time for collecting is during the middle 

 and latter parts of the month of May. The writer has collected 

 eggs as early as May 3, and as late as June 5, but these extremes 

 mark the beginning and closing of the early and late seasons." 

 Unless the dates given are for newly-laid eggs, which would 



