CHAPTER XXIII. 

 SPAWNING. 



" I marvel how the fish live in the sea. 



Why, as men do a-land ; the great ones eat up the little ones." 



PERICLES. 



A FEW general words will suffice to show how much room there is for 

 interesting inquiry in connection with the reproduction of fishes, and 

 to what good use information on the subject can and has been turned. 

 Most readers will be aware that in the case of salmon and trout the 

 female produces eggs without any connection with the male, and when 

 they are ripe within her, scoops out a hollow in the gravel to receive 

 them, and as she exudes them the male or cock salmon, who waits 

 upon her, ejects over them a milk-like fluid called milt, which fertilizes 

 them, and in which the spermatozoa can be detected by the microscope. 

 The ova of trout are covered with an adhesive matter which makes 

 them keep more or less together, and therefore more within the influence 

 of the milt, than if they were separated, and which makes them adhere 

 to stones, so that they are not in danger of being washed down, even 

 by a strong stream, and do not need to be covered as was formerly 

 thought. Again the spermatozoa are observed under the microscope 

 to radiate in the most regular order, so that nothing escapes them. 

 This manner of breeding makes it comparatively easy for man to 

 capture male and female fish, express the ova of the latter when ripe 

 into a bucket of water by very gentle pressure of the stomach, and 

 then similarly cause the male to emit milt, and stirring the two up 

 together, to fertilize the eggs, and hatch and rear them under protection. 

 It has been calculated that, when exposed to the ordinary vicissitudes 

 of nature, only one in a thousand salmon ova ever becomes a fish fit 

 for the table ; whereas man has learnt by artificial means to bring about 

 three quarters to maturity. 



THE ROD IN INDIA. Z 



