TRAKSACTIONS OF SECTION D. 



765 



better price in the market than fish which are smaller. It takes no account of the 

 question as to whether or not these fishes have ever spawned, and so contributed 

 to the natural supply or up-keep of their species. 



Our contention, therefore, is that, in all resolutions in which the line between 

 marketable and undersized fish is drawn, that line should be the one separating, 

 at the same time, the sexually mature and the sexually immature fish ; and, 

 further, that no protective measure of the kind referred to can possibly be of any 

 ultimate value unless the fish are protected till after their first spawning season. 



Further, Dr. Fulton's investigations have shown that, taking flat fishes as a 

 whole, females are much more numerous than males. A matter of equal, if not 

 greater, importance is the statement that, without exception, males were found 

 ripe at a smaller size than the females. 



Thus Fulton's figures show that in 23 males and 45 females (taking the turbot 

 as an instance) the average length in inches of males is 16-8-5, in females 20-83. 



It would appear clear from these observations, which have been verified over 

 and over again, that if any resolution dealing with the capture and sale of immature 

 fish be based upon the sizes at which the females alone spawn for the first time, 

 the smaller male fish, which are also less numerous, need not be taken into 

 consideration, since in proportion they will be protected to a greater extent than 

 the females. 



This opinion is held by Mr. Holt, Mr. Cunningham, and by myself, but Dr. 

 Fulton still inclines to include males. 



The appended table is arranged so as to compare the results from the four 

 districts mentioned, and includes also the sizes agreed on at the last fishery 

 conference. 



It is necessary to mention each district separately, since the sizes at which tbo 

 various species become mature differ very considerably on the different coasts. 



The figures under heading E. of Scotland are from Br. Fulton's reports, those 

 marked North Sea from Mr. Holt's. The "VV. of Ireland figures are also furnished 

 by Mr. Holt, but owing to a confusion in some of the records from which these 

 were derived these sizes are given with some reserve. 



It must be recollected that Dr. Fulton's figures include male as well as 

 female fish. 



The size of Plymouth fish are given in each case a little above that of the 

 smallest specimens found mature, thus allowing for variation of individuals. 



Pari II. On the Relation of Size to Sexual Maturity, (i) North Sea Grounds, 



Bij Eexest W. L. Holt. 



I append a series of tables in support of the size-limits prepared for this arca^ 

 giving the results of the examination of a number of fish at what appear to be 

 the critical sizes. 



I have used the term ' immature ' to denote fish in which the testes or ovaries, 

 show no signs of reproductive activity, and which, to the best of my belief, have' 

 not reproduced their species in any previous season. 



In the case of most species 1 find little difficulty in distinguishing between 

 immature fish and such as have already spawned, since in the case of the latter the 



