THE COMMON BKOWN TROUT. 233 



considering that there are nearly 200 species of these, it is evident that 

 the selection of suitable flies which I have made in the succeeding pages 

 does not comprise more than a small integral quantity. These two orders 

 are subdivided : the Neuroptera into the ephemeridce (May flies, &c.) and 

 perlidce (as stone and willow flies), and the scalidce ; the Trichopt&ra, so 

 far as our waters are concerned, into the phryffanidoe only, that is, if the 

 " silver horns " be excepted. 



Apart from these two orders, the other flies most used belong to the 

 coleopterous or beetle (sheath winged) kind (of such are the Marlow buzz, 

 the fern fly, and the peacock), and the diptera, or two winged (as the 

 cowdung, black gnat, gravel bed, &c.). The most of these are, however, 

 land insects. 



The two families, however, on which the hopes of the angler mainly 

 rest are the ephemeridce and the phryganidce. Of these I shall first refer 

 to the ephemeridce, and as the May fly (Ephemera vulgata) presents all 

 the characteristics in fullest fruition of the family, to this beautiful 

 insect will I specially point. 



The May fly presents items of life history of a more novel character 

 than most of its compeers. The butterfly's life, briefly, is as follows : 

 First, it is an egg ; this, when hatched into life, becomes a caterpillar 

 or larva, from the Latin, meaning a mask. In this larva state it con- 

 tinues some time, until the period for the third change approaches. It 

 then seeks an obscure corner, and a kind of hard skin spreads over its 

 body and incloses it as in swathing clothes. Hence pupa, from the Latin, 

 signifying infant. Some of these pupae, from being of a golden colour, 

 have been termed chrysalids, from a Greek word having a similar 

 meaning. After remaining in pupa state for a greater or lesser time, 

 according to species, it emerges in all its mature beauty, and this last 

 stage is that termed the imago. These are the embryonic developments 

 of an ordinary lepidopterous insect, and a more admirable and interesting 

 series of changes cannot be imagined. 



The Ephemera vulgata goes through a series of changes like these 

 enumerated, with the addition of a fourth, termed pseud-imago, or false 

 image, immediately preceding its complete maturity. To trace the 

 ephemeras ab ovo, the eggs are dropped in the water in immense numbers, 

 and are devoured by the crustacea and other foes in huge quantities, but 

 a sufficiency remain to become larvae, and they in turn wage ceaseless 

 and devouring war upon fish eggs, maintaining the grand and unvarying 

 balance of life which obtains all over the multiform creation. The larvae, 

 being aquatic insects, are endowed with gill-like appendages extending 

 down each side of the abdomen ; these are continually in motion, and 

 the air is separated from the water and conveyed to the tracheae. The 



