of the Fishery Board for Scotland. 



Ixv 



exceed, and usually greatly exceed, the number retained, but the 

 proportion varies very greatly. 



MarJcing Experiments. 



The number of food fishes which were " marked " and liberated 

 during the period amounted to 2328, of which 1915 were plaice, the 

 others including eleven species of flat-fishes and round fislies. The 

 fish taken in the trawl are selected according to their condition of 

 liveliness and apparent vitality, and after being kept in tubs of 

 running sea water for some time the best are picked out and 

 " marked," usually being returned to the tubs for several hours, after 

 which the suitable ones are liberated at certain " stations " or selected 

 localities. The mark consists of a numbered vulcanite disc, attached 

 by a silver wire. The main objects of the marking experiments are 

 threefold : — (1) to ascertain the migrations of the fish ; (2) to 

 determine the rate of growth ; (3) to furnish information as to the 

 extent or intensity of fishmg on different grounds or parts of the sea. 

 Of the fishes marked and liberated, 503 were caught later and 

 returned, 500 of them being plaice, of which 26 per cent, were thus 

 recaptured. It is unfortunate that the attempts to mark the haddock 

 were unproductive of results, owing to the exceeding tenderness of 

 this fish. Special precautions and a special mark are now being 

 employed in such cases, and it is hoped that information may be 

 obtained as to the movements of this important food fish. 



Observations on Reprodiidion of Food Fishes. 



In addition to the information acquired by ascertaining the con- 

 dition of the reproductive organs of a large proportion of the fishes 

 taken in the trawl, hauls were made at a large number of stations 

 with special nets, with the object of determining quantitatively the 

 abundance of the floating eggs of the various species at different 

 seasons and at various localities. Drift-bottles were also thrown 

 into the sea, containing numbered cards, in order to throw light on 

 the course and rate of the currents by which the floating eggs are 

 carried from the areas where they are spawned, and the floating 

 larv« after the eggs are hatched. 



Eeports on various branches of the investigations are in course of 

 preparation. The records on board have been very efficiently kept 

 by Mr. George H. Smith, and Captain Murray has spared no effort lo 

 have the work promptly carried out. 



We have the honour to be, 



Your Lordship's most obedient Servants, 



ANGUS SUTHERLAND, Chairman. 



T. B. MORISON, Beputy-Ghairman. 



D'ARCY W. THOMPSON. 



BEEADALBANE. 



JAMES ARCHIBALD. 



JOHN H. IRVIN 



MALCOLM SMITH. 



DAVID T. JONES, Secretary. 



