170 STOCKING OF RIVERS. 



ova of the earliest age were all killed in the 

 trials ; those most advanced, the oldest, mostly 

 escaped with retention of life.* 



AMICUS. Your experimental results are Letter 

 than my analogical conjectures. Your opposite 

 analogy would hardly have satisfied me, but 

 your facts do completely. I shall take a note 

 of them and hope to profit by them practi- 

 cally, that is, by introducing fish into waters 

 seemingly fitted for them, such as the charr and 

 the grayling, at present unknown in them. 



PISCATOR. Such attempts are laudable, and in 

 many instances, probably, will be rewarded with 

 success ; it is too much to expect that they will 

 invariably be so; for as with plants so with 

 animals, with fishes, there are physical cir- 

 cumstances of locality difficult of appreciation, 

 favourable and unfavourable, the effect of 

 which can only be ascertained by actual ex- 

 perience ; and which require to be taken into 

 account in considering the distribution of 

 species. 



AMICUS. There is another point on which 



* For an account of these experiments, see the 

 " Philosophical Transactions," for 1856 ; and the "Pro- 

 ceedings of the Royal Society, vol. viii. p. 27. 



