)•■■ 



... o- 



)•• 



3 



)•• 



... 34 



)•• 



... 22 



)•• 



... 12 



SEA-FISHERIES LABORATORY. 263 



rings an opaque zone and a translucent zone are added to 



the otolith. By counting the number of opaque rings, it 



it possible to arrange the fishes in the groups 0, I., II., 



III. and IV. according to the number of these zones 



outside the dark nucleus of the otolith. Of the total 



number of marked plaice returned 66 have been examined 



in this way, and may be grouped as follows : — 



Group (in the first year of life). 



I. „ ( ,, second,, . 



II. „ ( ,, third „ 



III. ,, ( ,, fourth „ 



IT. „ ( „ fifth „ s 



The numbers examined are, of course, much too 



small to enable a satisfactory estimate of the size of the 



fishes at each year to be made. I give the averages 



calculated for what they are worth : — 



Females in Group II., average length = 9*3 inches. 

 ,, ,, 111., ,, ,, = Vd'Z ,, 



TV — 14 



Fish Caught in Extra-Territorial and Intra- 

 Territorial Waters. 



There were almost exactly as many marked fish 

 recaught outside as in the territorial waters. Such a 

 statement possesses, however, no significance since, if it 

 is the case that an offshore migration takes place in the 

 summer months and an inshore and alongshore migration 

 in the winter months, it obviously follows that the 

 numbers of marked fishes caught inside and outside the 

 territorial limits depends on the time of year at which 

 most of the marked fishes were liberated. If we mean by 

 " winter " the months October to March, and by 

 " summer " the months April to September, we then 



