A LITTLE ENTOMOLOGY 61 



freely about from place to place, dragging behind 

 it what is to all appearance a huge burden. 



In time the larva pupates or enters into a period of 

 rest preparatory to changing into the winged state. 

 During this time it does not feed or move about, 

 but, being still alive and wishing to remain so, it 

 must breathe and also protect itself from its enemies. 

 It effects this double purpose by closing up the 

 entrance to its home by means of a sieve or grating 

 through which water carrying the requisite oxygen 

 can freely pass, but by which irritating foreign 

 matter and predaceous creatures are excluded. 

 After awaking from its sleep the larva, by its own 

 characteristic method, sets out for the air ; there 

 it undergoes the great change and emerges fully 

 fledged. There is no intermediate stage corres- 

 ponding to the sub-imago of the Ephemeridcz. 



Though many caddis-flies rejoice in the gloaming, 

 and some are even more nocturnal in their habits, 

 others again select the full light of day for their 

 aerial adventures. They are none too strong upon 

 the wing ; some flutter bravely enough, while their 

 relatives seem to find all necessary pleasure in 

 crawling over or remaining quiescent on old wood 

 beside the water. They are never far from the edge 

 of stream or loch, and all lay their eggs on the water, 

 therefore trout know them well. 



It is quite possible that some species of sedges have 

 a flavour that is not to the trout's liking. There 

 is a sedge-fly commonly seen floating on Loch 

 Leven ; the boatmen call them " hornies," probably 

 from the long antennae which distinguish the order 

 Trichoptera, and some at least declare that trout 

 absolutely ignore them. Whether it is true or not 



