354 



TRANSFORMATIONS OF INSECTS. 



beautiful and most delicate membrane, which it has to escape 

 irom before it takes to flight. When thus enclosed it is called 

 the pseud-imago, in contradistinction to the imago or the perfect 

 insect. 



The engraving represents the metamorphoses of the May fly. 

 In the water, amongst the weeds, there are larvK and a large 

 nymph, on a leaf at the side one is escaping from its covering, and 

 the perfect insects are flying over the lake. 



The European EphemeridcB have been carefully studied by 



LARVA AND PUPA OF AN Ephemera. 



Pictet, and the kinds which can properly be united together, on 

 account of their having numerous transverse nervures on their 

 wings, and their abdomens being terminated by three bristle- 

 shaped hairs, are called Ephemera. The commonest are the May 

 flies, which appear in early summer in such enormous quantities. 

 The adults have a short life, which only lasts a few hours ; they 

 never take any nourishment ; and their beautiful wings, which 

 are exquisitely made, and delicately marked with brown spots, 

 appear almost to be wasted, so short is their time of flight. Their 

 larvae and nymphs, like those of the species which are allied to 

 them, are long and cylindrical, and nave projecting jaws and 



