367 



Notes on Recent Experiments relating to the Growth 

 and Rearing of Pood-fish at the Laboratory. 



Reference has been already made in tlie Report of the Council 

 to the successful (artificial) fertilization and hatching of the eggs of 

 the sole, and to the study of the plaice eggs which were naturally 

 fertilized and hatched in the aquarium. With regard to the 

 rearing of lobsters, Mr. Weldon and Mr. Fowler have contributed 

 the followiug notes on their experiments : 



I. The Rearing of Lobster LARViE. 



In the intervals of other and more pressing work we have made 

 during the months of June and July a few experiments on the 

 rearing of lobster larvae ; and although for various reasons these 

 experiments were not successful, a few notes on the methods pur- 

 sued and the conclusions deduced may prove of use to others 

 engaged in the same task. It is possible that the cause of failure 

 was merely that the eggs had suffered in being brought in^ from the 

 struggles of the mother lobsters ; certainly a very large number 

 of larvae died in the act of hatching, too weak to extricate them- 

 selves from the shell. The shortness of the hatching season, 

 however, prevented the undertaking of new and special arrange- 

 ments for carrying them. Other possible causes of failure were 

 want of space and the difficulty of providing a suitable food. As 

 to the question of space, most pelagic organisms cannot bear to be 

 confined within narrow limits, whether vertical or horizontal ; they 

 must, if they are to thrive, have a large superficial range, as well as 

 a considerable depth of water to which they may sink when such 

 physical conditions as light and heat demand it. As the Associa- 

 tion had unfortunately no funds to place at our disposal for this 

 special purpose, the largest body of water available was a tank of 

 sixty-three feet superficial area, and containing about 600 gallons ; 

 the water was in constant circulation, and formed part of the 



