24 FLY-FISHING AND FLY-MAKING. 



head, allows the fish to perceive vibration instantly front 

 the whole of its surface, as well as immediately from the 

 outer part of the head. The trout is specially furnished 

 in this way, and the interior mechanism of the ear in all 

 fishes is very beautifully adapted to their requirements. 

 The curious oolith, or brain ivory, possessed by nearly all 

 fishes, forms the bones guarding this aural development, 

 and sometimes these are of exceeding delicacy and beauty. 

 In the loaches there is a connection between the ear and 

 the air cavity, situated in the anterior part of the head, 

 which may be supplementary to their impaired sight in 

 daylight, and the same peculiarity is noticeable in the 

 Cobitis Barbatula, a small loach of English streams, and 

 the Coitus gobio, a bull-head. Both these are almost 

 exclusively night feeders. 



Sound travels in air at the rate roughly of eleven 

 hundred feet per second ; in water, accurate experiments 

 fix it at over five thousand feet in that space of time. 

 When quite a youngster I satisfied myself of its extreme 

 rapidity and the great conducting power of water, on 

 several occasions, in the following way : The fishermen 

 of the Thames use an iron-shod pole, termed a ryepeck, 

 to fix the punt when fishiag, and this experiment was 

 made : A friend took a boat and rowed down on a long 

 clear reach of water to the end of a measured mile. I 

 remained at the starting point, divested of my clothes. 

 As he got to the end of the mile I stepped into the water, 

 which was about up to my armpits, with a small red flag in 

 my hand, and as soon as he saw my head disappear under 

 the surface it was agreed he should ram the iron down, 

 and I was to exhibit the flag on hearing the sound. Well, 



