TROUT HABITS; LURES AND USE 



the erect-winged or Ephemeridce and the flat- 

 winged (Phryganidce, Muscedce, etc.). Of the 

 latter there are many varieties, some land and 

 some water flies. The water flies are of chief 

 interest to the angler. Hatching under water, 

 they rise to the surface, take to the air, sporting 

 on or near their native element, and live but a 

 few days to fulfill their procreative function. 

 Of the up-wings there aj*e four species: Olive 

 Duns, Iron Blue Duns, large browns (March 

 Brown, Turkey Brown, etc.), and the May-fly 

 or Green Drake. The prevailing temperature 

 of the atmosphere and water at the time of the 

 larvse and pupse arriving at maturity influences 

 the color of the insect, says Mr. Foster. For ex- 

 ample, of one race but many colors like man 

 all the Olive Duns are the progeny of the Red 

 Spinner, and all that live to maturity become 

 spinners. [Other English observers state that 

 the color also differs on different waters and on 

 different sections of the same stream, under 

 like conditions of temperature; and some 

 authorities refer as "spinners" to any slim-bodied 

 long-legged flies having two long narrow wings.] 

 Each of these varieties of the up-wings lives 

 three days after having ascended from the 

 river's bed and burst their "swathings." They 

 then cast their skins, reappearing as spinners, 

 in which final stage of their existence they are 

 the fathers and the mothers of the new genera- 

 139 



