130 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 



fishermen reported that several very large plaice had been 

 captured in the Barrow Channel. The sizes of these fish 

 far exceeded those of any flat-fish they had previously 

 taken. The men suggest as a very probable explanation 

 that they were some of our liberated plaice. Capt. 

 Wright also secured one or two of these large fish while 

 trawling for flounders for the tanks. It is quite possible, 

 then, that the large plaice set free at the end of each 

 season remain in the vicinity. 



When selecting adult plaice for the tanks we depend 

 largely on their size, and hitherto all under fourteen 

 inches in length have been rejected. This size is 

 probably a good average one, but it is evidently not 

 always the minimum even for females. This was clearly 

 demonstrated in the spring of 1906. In March, when out 

 with the " John Fell " collecting material for the classes, 

 two mature female plaice were captured in the same haul. 

 One of these fish was nineteen and a half inches long, and 

 the other was only ten and a half inches. Later on in 

 the month two more mature plaice were captured in the 

 same area as the previous ones. The latter were both 

 eleven and a half inches long. These fish were brought 

 alive to Piel. 'They all produced eggs which fertilised 

 and developed quite formally. The fish were captured 

 between Walney and Isle of Man in the area known as the 

 " Top end of the Hole," on March 13th and 20th. 

 According to Mcintosh and Masterman* plaice appear to 

 have very definite spawning grounds, always well offshore 

 and at a depth of about twenty fathoms. Under artificial 

 conditions we find it is possible to get them to spawn in 

 much shallower water. At Port Erin the fish spawn 

 freely in a pond with a maximum depth of ten feet. At 

 the Bay of Nip/g Hatchery, belonging to the Fishery 

 -British Marine Food Fishes, p. 364. 



