56 BRITISH FRESH-WATER FISHES 



other, Nature effects that both these fish shall hold its place 

 in the population of the sea hold it, and no more. 



The reproduction of the perch is conducted on the spend- 

 thrift or broadcast system. It is usually calculated that a 

 female perch of half a pound in weight contains upwards 

 of a quarter of a million eggs, while Picot, of Geneva, reported 

 that the ovary of a single female weighing one pound contained 

 no less than 992,000. At this rate, the crop of spawn in 

 a single season from a shoal of perch suggests an amazingly 

 rapid increase in the species ; but such is the avidity of water- 

 fowl, water-insects, and fish of other species for this gratuitous 

 supply of food, that only a small percentage of the eggs ever 

 reach the hatching point. Even so, towards the end of summer 

 countless numbers of perch fry may be seen swarming in quiet 

 corners and shallow bays ; and these, again, have to run the 

 gauntlet of innumerable foes, including, as mentioned above, 

 their own blood relations. 



While on the subject of perch fry, I may put on record an 

 incident which, occurring many autumns ago, set at rest for 

 The hear- ever, so far as I, at least, was concerned, the vexed 

 ing of fish. problem whether fish can hear. The fact that fish 

 possess ears might be assumed as an answer to the question, but 

 the additional facts that they possess no external ear-covers, and 

 that the skin covers the opening to the auditory chamber, 

 are quite enough to account for the prevalent belief that fish 

 have no ears, and therefore cannot hear. The fry of perch 

 were the means by which I received ocular demonstration to the 

 contrary. 



In still, bright October weather I had set up my easel on 

 the shore of Loch Ken, in Galloway. The water was calm and 

 very clear, and as I was painting I noticed that near the 

 margin it was peopled by multitudes of tiny perch. Towards 

 the afternoon a party of partridge-shooters appeared in a turnip 

 field fully three-quarters of a mile from where I was sitting. 

 Presently one of them fired a shot. The report came clearly, 



