FLY FISHING FOR TROUT 35 



the said pupa the insect appears in its semi-complete 

 state, it has to undergo yet another change before it 

 becomes the perfect Mayfly. 



After having divested itself of its pupal covering, 

 it flits gently to some branch or reed, whereon it rests 

 while waiting for the final metamorphosis. It is sup- 

 posed, and I think reasonably, that this is effected by 

 the action of the sun and air. Presumably the dura- 

 tion of this operation depends largely on the condition 

 of the atmosphere. After a time a further skin splits 

 open, and the Mayfly comes forth fully developed, 

 in all its perfection, to join the dancing throng of in- 

 sects which perform their wonderful gyrations over the 

 waters. After so protracted a process of creation, it 

 might be imagined that the Mayfly would be granted 

 a fair lease of life, supposing it to escape the onslaught 

 of anglers, birds, and fish; but, as has been said, 

 a very brief existence is its lot. It lives but a few 

 hours. The Rev. J. Wood states, in ' Insects at Home,' 

 that ' the life of the Mayfly in its normal condition 

 is supposed never to exceed the limits of a single 

 day.' It must be remembered that this insect does 

 not possess a mouth, or only a very imperfect 

 one, and therefore cannot eat : a fact which lends 

 additional mystery to its existence. While it lives 

 it loves : that seems the principal reason for its 



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