60 



The first larvae were observed on the 8th of March, the 14th 

 day after spawning and the mean temperature of the water was 

 6'8° C. The time between spawning and hatching was 

 found to vary. Some of the eggs spawned on the 10th and 14th 

 of April and kept in separate glass vessels hatched on the 21st 

 and 2oth respectively, that is on the 12th day from spawning. 

 During this period the mean temperature of the water was 

 8'1° C. Others spawned on the 6th of May hatched on the 

 15th or the 10th day from spawning, the mean temperature of 

 the water being 9"9° C. 



From the observations made, spa^^ming took i^lace in all cases 

 in the morning, generally before 9 o'clock. The plate accompany- 

 ing this account shows the growth made by the embryo from 

 day to day for a period of 14 days between spa^vning and hatching. 

 The number of eggs in the tanks was so large that it was 

 necessary to take some thousands to sea in order to give them a 

 chance of hatching. Samples have been taken representative of 

 the stages of development for each day and it is hoped that this 

 material will be of use for an account of the development of the 

 plaice. 



