Distribution of Plaice Eggs. 9 



y. — When the embryo is more than half round the diameter of the 



yolk. 

 h. — When the embryo is coiled completely round the egg, that is, 



just shortly before hatching. 



As the eggs float passively in the water those in the first stages of 

 development ara not only nearer to the date of spawning but are more 

 likely to be nearer to the actual spawning area than those which have 

 passed into the later stages of development. In other words, the area 

 of distribution of the eggs in the later stages of development is wider 

 than the actual spawning area. A study of the distributions of the 

 eggs in the various stages of development may therefore show not only 

 the general effect of the currents on such passive objects but also the 

 conditions under which the tiny larvae are hatched out. 



The extensive observations made by the " Goldseeker " during the 

 month of November cover a considerable portion of the area within the 

 fifty-fathom line, but no plaice eggs were found so early in the season. 

 One may conclude with certainty that few, if any, plaice spawn in the 

 Northern North Sea in November, 



The first records of plaice eggs in the plankton of the " Goldseeker " 

 collections occur in December. They were made at three different 

 localities during the ten years, and they are of sufiicient importance to 

 be given in some detail. 



Records of Plaice Eggs Collected during the Month of 



December. 



These are the earliest records for Scottish waters. Three are from 

 the Dornoch Firth area (57° 53' N. ; 3° 48' W.) and one is from East of 

 May Island (56° 16' N. ; 2° 17' W.). The Dornoch Firth area, which 

 is one of the earliest and most important spawning areas of the plaice 

 on the East Coast of Scotland, has been visited with great regularitv 

 during the last ten years, and the following tables shows how the 

 h 



