NOTES ON THE MONTHS FOR FLY-FISHING. 197 



somewhat during this period. In August the Iron Blue 

 assumes a more olive cast upon the body; in September 

 and October the precise shade and color in wing, leg, and 

 body is the same as the Olive Dun of the same period, 

 having a rusty shade upon the body precisely similar, the 

 only difference being in point of size. These little duns 

 are sometimes erroneously supposed to be half-matured 

 Olive Duns; but flies do not grow or expand gradually, 

 they are full sized when they quit their sheaths, as in the 

 larva and pupa state they feed voraciously, laying up an 

 internal store which lasts them the remainder of their 

 existence, as we have elsewhere observed. The Jenny 

 Spinner is a good killer, even when the water is extremely 

 fine. The Yellow Dun of May is very prevalent on fine 

 days, when it should be on the cast. The Alder fly is 

 very abundant from about the last week in May to the 

 middle of June. It is a flat- winged fly, and comes from 

 a water nympha. The wings are of a dull brown, veined, 

 the body being a dark claret, and the legs of a rusty black 

 shade. It is a great favorite with trout and chub, par- 

 ticularly towards evening. The natural insect may be 

 used for dibbing, it being a large fly, though slightly 

 varied in different localities. The Black Gnat is a very 

 small fly, which is a great favorite with trout and gray- 

 ling, when fully on the water. The fisherman's Black 

 Gnat is a small winged fly, and is not to be confounded 

 with the angler's plagues or pests, so prevalent at the 

 latter part of the season; indeed, the naturalists aver that 

 it is not a gnat in reality, that term being correct only in 

 the case of the minute black smuts referred to, which re- 

 semble nothing better than a fine speck of soot. The 

 copies, however, of the Black Gnat, generally speaking, 

 are much too large, being nearer the size of a Blife Bottle. 

 The same observation also applies to the Iron Blue, the 

 Jenny Spinner, and other small flies. Just when the 

 May fly begins to appear the gnats generally come on in 



