36 



Fish Hatching. 



A stock of large plaice were collected in Luce Bay in 

 October, and in due course conveyed to Piel. Adult flounders 

 were trawled in Barrow Channel towards the end of 1920. 



The plaice and flounders both began to spawn on the 6th of 

 March, eighteen days earlier than in 1920, and continued to 

 produce eggs until 30th April. The last fry (plaice) were set 

 free on 24th May. Altogether 1,150,000 plaice eggs and 

 12,500,000 flounder eggs were collected and incubated; 

 1,000,000 plaice fry and 11,000,000 flounder fry were hatched 

 and set free. 



Re-survey of Shellfish Beds. 



The mussel beds of the Ribble, in the vicinity of Lytham, 

 were examined by Mr. W. Birtwistle and myself in July and 

 again in November, 1921. On the first date a topographical 

 survey of the sewer outfalls and their relation to the mussels 

 was made. On the second visit samples of the mussels were 

 collected and examined for sewage contamination. Reports 

 were submitted in each case and were published in the Report 

 of the Superintendent, Dr. Jenkins, for the quarters ending, 

 30th September and 31st December, 1921. 



