78 THE BROOK BOOK 



had often watched the latter part of this transfor- 

 mation, while waiting for the early morning boat 

 at the riverside station, and had formed the notion 

 that between five and six o'clock in the morning 

 was the chosen time for molting. But it was now 

 two o'clock in the afternoon. 



The principal features of the May-fly's early 

 life have been told in a previous chapter. The 

 insect never gets far from its native stream, even 

 after it reaches the winged stage. It dififers from 

 most other insects in having a short period of ex- 

 istence in which it is neither aquatic nymph nor 

 aerial adult. While in this "sub-imago stage," as 

 it is called, the insect resembles very closely the 

 adult form. It is full size and has fully developed 

 wings and legs. After once witnessing the trans- 

 formation there on the hotel veranda, it was not 

 difficult for us to distinguish between those which 

 had passed the final molt and those which had 

 not. The adults were more lively, and their wings 

 were thinner and more brightly iridescent. The 

 whole appearance of the sub-imago is dull and its 

 behavior awkward and stupid. The anal filaments 

 are short and stout. The colors are dim, literally 

 as if seen through a thin veil. When the final 

 molt has taken place the creature emerges full of 

 spirit. The movements are quick and the colors 

 clear and even brilliant. The legs are slender, 

 almost useless, the anal filaments taper delicately 

 and are twice and sometimes thrice their previous 

 length. They are often prettily marked with light 

 and dark on alternate segments. After shedding 



