ARTIFICIAL HA TCHING OF MARINE FOOD-FISHES. 261 



gently lowered into the water, and the little fishes soon 

 spread themselves around. 



On the other hand, the Americans kept the fry of the 

 cod only from twelve to forty-eight hours after hatching. 

 Here it was thought prudent to liberate the larval plaice at 

 distances varying from two to six miles from shore, so that 

 the usual transformation might ensue before the latter was 

 reached. Under present circumstances, no question could 

 be raised as to the retention or dismissal of the larval fishes, 

 since no pond was available. Moreover, it is an open 

 question whether the retention of the young fishes — until 

 they have attained some size — would be a marked advan- 

 tage. The expense would certainly be greater. Nowhere 

 can these minute fishes find such nourishment as unfailingly 

 meets them in the sea, and nowhere will they grow more 

 rapidly. It is true that, translucent though they be, their 

 natural enemies will reduce their numbers, but such is un- 

 avoidable. For the elucidation of the life-histories, again, 

 of some, e.g., the haddock and lobster, and the rate of 

 growth of others, a certain number can be experimented 

 with in tidal-ponds, as soon as these are available- 

 There is, perhaps, no urgent need for taking the round 

 fishes in hand at present, since cod and haddock are in fair 

 abundance, but if it were possible to increase the numbers 

 of halibut, turbot, and soles, the benefit to the fishing com- 

 munity and the public would be great. The difficulties 

 connected with the artificial hatching of these on a large 

 scale are somewhat greater than in the case of the round 

 fishes, but it is to be hoped they will be overcome. If it be 

 found that the sole will live and breed in fresh water, and 

 that the turbot, the brill, the bass, and the grey mullet— 

 as stated so far back as 1837 — will live in a five-acre lake 

 so Iresh that cattle drank it for nine months of the year, en- 

 couragement of a welcome kind is given to these hatching 

 operations. Again, by the acclimatising of certain fishes, 

 e.g., the Baltic herring, to fresh water, a more successful 

 means of transmitting the species to distant seas may also 

 be offered than by the attempt to forward the eggs. 



Amongst the pelagic eggs, besides those above men- 



