12 THE ANGLER-NATURALIST. 



frequent situation) — their position^ however, being always 

 adjusted to suit the habits of the particular fish. The 

 external surface of the eye itself is nearly flat, but the lens 

 is spherical — a structure which, in a dense medium, affords 

 the greatest power of vision at short or moderate distances, 

 rather than a very long sight. When water is clear and 

 undisturbed, however, the sight of fishes is very acute ; and 

 for this reason it is that a ruffled water is always prefer- 

 able to a smooth one for purposes of fishing. I believe 

 myself that the sight of fish in clear water is longer than 

 is generally supposed. Standing by the side of a Scotch 

 loch in bright calm weather, I have frequently remarked a 

 Pike basking at from fifteen to twenty-five yards from the 

 shore, and could plainly perceive that the observation was 

 mutual. The fish, after fixedly regarding me for a few 

 moments, has generally backed slowly away into the deep 

 water, disappearing so motionlessly — if I may use the ex- 

 pression — that the eye was hardly conscious of its retreat 

 until it became aware that it had vanished. Moreover, it 

 is well known that a basking Chub will sink upon the 

 flitting of a swallow across the river ; that in ponds where 

 Carp are habitually fed by visitors, the former will follow 

 the latter about for the expected largesse ; and that in- 

 stances have been authenticated — in several cases under 

 my own observation, elsewhere detailed — in which fish 

 (evidently recognized their keepers, as well by sight as by 

 sound : thus clearly leading to the inference that, when 

 ice can see the fish, the fish can see us. 



