128 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 



theory and perfect practice must be in accord) he is the 

 better equalizer of the disturbed balance when he uses for 

 the hatchery the eggs of fish which would not have 

 spawned in a state of nature — that he can do by obtaining 

 ripe spawn from the fish trawled for market at the spawn- 

 ing season. This plan has been adopted in some hatcheries ; 

 and in our own experiments at Port Erin and at the Piel 

 hatchery. It is the least expensive method of getting 

 spawn, but it is open to several difficulties and objections. 

 The other method is to collect the parent fish beforehand 

 and keep them in ponds until they spawn. It is the 

 method adopted in Norway and to a large extent in the 

 United States, and which Mr. Fryer has tried to show 

 results in a comparatively small number of fry per fish 

 used. 



I shall not pursue the matter further. There is no need 

 for me to defend or expound the methods and statistics of 

 the United States Fish Commission. Their own officials 

 are very well able to answer for themselves, and very 

 probably they will do so — if they think it worth while.* 



I have merely gone into some of the questions raised in 

 Mr. Fryer's article because it seemed to me that he was 

 modifying the statistics in an unjustifiable manner, and 

 drawing conclusions with which I could not agree, and 

 which might have some bearing upon our procedure in this 



* It may be well before leaving this part of the subject to point out that in 

 the appendix (a Manual of Fish-Culture, based on the methods of the United 

 States Commission of Fish and Fisheries, Washington, 1898) to their last 

 published report, which appeared only a few months ago, the United States 

 authorities remark in regard to their artificial propagation of the Cod: — "The 

 unmistakable economic results which have attended these efforts warrant all 

 the time and money devoted to them and justify the greatest possible 

 expansion of the work." I have also more recent letters from the Com- 

 missioner and the Naturalists on his Staff making detailed statements to the 

 same effect. 



