76 ON ARTIFICIAL FLIES. 



This work not being in any way intended as a 

 treatise on entomology, and the classification of the 

 natural flies according to Order, Family, Genus, 

 and Species having been so thoroughly and accu- 

 rately explained by Ronalds, it is not proposed to 

 touch on this branch of the subject. The flies 

 bred in the water may, with very few exceptions, 

 be considered as belonging to one of two great 

 families, the Ephemerae and Phryganidae. 



The Ephemerae, to which family all the duns, May 

 flies, and in fact all upright winged flies, according 

 to the authority of modern entomologists, belong, 

 are hatched in the opaque-winged or " pseud- 

 imago " state, and, excepting in the case of the 

 May flies, are, in this state, usually styled " duns." 

 After a short time, varying in different species, and 

 increased or diminished according to temperature, 

 moisture, &c., from a few hours to two or even 

 three days, they shed the whole of their external 

 covering of wings, body, legs, and even tail, and 

 emerge in the transparent-winged spinner or 

 " imago " dress. The colour of the body has 

 usually changed very considerably, the seta or 

 tail increased in length to an extraordinary extent, 

 the wings are transparent, and the fly is altogether 

 more delicate in ^outline and more brilliant in hue. 



Thus the various shades of the olive dun in its 

 perfect state become red spinners, with bodies of 

 all tints of red brown, from a pale burnt sienna to 

 a dark crimson ; and the iron blue, unswathed of its 



