104 HISTORY OF THE Pll KM \\.KA. 



into a pupa (the word pupa signifying a puppet, or doll, 

 from the swathed and swaddled appearance of the grub,, 

 with its wings, &c., bandaged about as it were) ; the change 

 in form is slight, but an important change has, never- 

 theless, taken place. Hitherto the creature has possessed 

 no sign of wings ; changing into the pupa state, it throws 

 off its skin, and another one is developed, and on tin- 

 shoulders are seen two excrescences, which are the rudi- 

 ments of the future wings. The pupa is larger than the 

 larva. The time which the larva and pupa dwell under 

 water varies in the different species from one to three 

 years, it is supposed. 1 At length, however, the insect 

 approaches to the change into the fly state, when it rises 

 to the surface or creeps to the bank, and there, splitting 

 off another case, at once emerges a fly. But even now it 

 is not a perfect insect, and is incapable of procreating its 

 species ; its colours are dim and dull, its motions heavy, it 

 dwells much on the surface of the water, and is an easy 

 and welcome prey to the eager fish. In this form it is 

 said to be semi-completa^ or only a half complete insect, 

 and is termed the pseudimago, or false image ; in the 

 May fly it is the green drake, and in the smaller species 

 is the dun of the angler. After a short time, however, the 

 fly throws off yet another complete casing, and emerges 

 larger, brighter in colour, with tail greatly elongated, 

 stronger and far more active a perfect insect, the imago 

 or image, at last The green drake has now become the 

 grey drake ; the last offices of the insect's life are then 

 performed, it consummates its existence, drops its eggs 

 upon the water, to the number of many hundreds, and dies. 

 The Phryganidje go through much the same process, 

 with the notable exception that they spring from the pupa 

 tote into the perfect fly or imago at once, not having to 

 pass through the pseudimago phase of existence. When 



1 From observations I hare made I hare reason to believe that the 

 May fly larva remains two years in the water. 



