BRITISH INSECTS 



nymph crawls out of the water when full-grown, the 

 skin enveloping it at once spHts asunder, and the winged 

 insect comes forth. This all happens very quickly, 

 and when the rise of the Mayfly takes place, the observer 

 is able to watch at close quarters this magic transforma- 

 tion. All is not complete even when the insect is clear 

 of its watery home, as another skin has to be discarded 

 before the perfect state is reached. For a few brief 

 moments the winged form pursues its airy course down- 

 stream. Many fall by the way, to be devoured by 

 trout and other fish, and those that do succeed in keeping 

 on the wing soon live their little day and cease to be. 

 But some, at least, are spared long enough to mate and 

 deposit their eggs, so that the future of the race is assured. 

 The fully-developed Mayfly has greenish-yellow wings, 

 with dark spots. The body is pale yellow, with some 

 dark lemon streaks on the lower part, and an almost 

 black thorax. It is interesting to notice that, although 

 it takes at least two years to acquire the adult state, the 

 perfect insect only enjoys a brief flight in the sunshine, 

 and then passes away. The larva feeds mostly upon 

 vegetable matter, but some species are partly carnivorous. 

 When the " rise " does occur, large numbers may be 

 observed emerging if the right moment is struck. I 

 have seen the air, ground, and water thickly populated 

 with the insects and their old nymphal shrouds, and 

 perhaps of all the amazing episodes associated with these 

 forms of life, the rise and fall of the Mayfly is one of 

 the most entrancing in the whole realm of Nature. 

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