REPORT OP THE COUNCIL, 1890. 359 



Oil the 13tli March this year the plaice in the aquarium were 

 found to be breeding. The Director and Mr. Cunningham collected 

 a large number of their fertilized ova and transferred them to 

 suitable hatching apparatus. The ova hatched out by the 18th 

 March, and the larvae were kept alive in specially isolated tanks till 

 April 2nd. By this time the yolk-sac was completely absorbed, but 

 the larvae, although apparently healthy, could not be induced to 

 feed. They died off very suddenly, evidently for want of food, on 

 April 3rd and 4th, having lived fifteen days after hatching. 



A second batch of ova was procured on March 28th, and the 

 eggs were hatched out on April 3rd and 4th. These larvse were 

 placed in a tank and fed with the pelagic organisms caught in the 

 tow-net. They paid no attention to this food, so on April 22nd 

 they were fed with crushed crab, which they appeared to like, for on 

 the following day their intestines could be seen full of food. In 

 spite of this they began to die on April 24th, and all were dead 

 by the 26th. 



Thus in the second experiment the larvae were kept alive twenty 

 days after hatching, a considerably longer period than in previous 

 experiments at Plymouth, and, what is more important, they were 

 induced to feed. These experiments show that some steps have 

 been made towards success. None of the larvae underwent meta- 

 morphosis, but Mr. Cunningham has procured some young plaice, 

 flounders, and brill, already " flattened,'^ and these are thriving in 

 the tanks and feeding regularly. 



Arrangements have been made with the Fishery Board for 

 Scotland for carrying on an investigation on the food of the common 

 sole in connection with the work done by the Board on the food of 

 other fishes. 



Mr. W. Bateson was working on the sense-organs and habits of 

 fishes, with the view of showing the possibility of using artificial or 

 preserved baits in sea fishing, from April to October, 1889. The 

 results of Mr. Bateson's investigations have been published in the 

 Journal, vol. i. No. 3. 



Mr. Weldon continued his investigations on the artificial rearing 

 of lobsters last year. His experiments were apparently turning 

 out successfully when an accident caused the loss of his larvae and 

 apparatus. This year the artificial rearing of lobsters is being pro- 

 ceeded with by means of a different form of apparatus suggested by 

 Dr. Fowler's successful method of raising the young of Idotea. 



In addition to his experiments on lobsters Mr. Weldon is engaged 

 on important scientific investigations on the variation and natural 

 history of the Decapod Crustacea. 



The following gentlemen and ladies have been engaged on inde- 



