REPORT OF THE COUNCIL. 103 



Hinder, and Sandette Light Vessels. D-nets and obliquely hauled tow- 

 nets were also used in the course of the voyage. 



Drift Bottles. — In February, 1910, in co-operation with Mr. Bidder, 

 drift bottles were put out along a line stretching E.N.E. from Spurn. 

 One hundred bottom drifters and two hundred and sixty-six surface 

 drifters were put overboard in all, the first at 5 miles and the 

 last at 88 miles from land. This experiment being conducted in an 

 area hitherto untouched in similar investigations, but which is known 

 to be a plaice-spawning ground, should yield results of considerable 

 interest. 



The Association is indebted to Messrs. Wilson for granting all 

 facilities for the work, and especially to Capt. French of the s.s. Zero 

 for very valuable assistance rendered during the voyage. 



B. LABORATOEY WORK. 



Reports are, or will shortly be, in the press dealing with the Trans- 

 plantation Experiments, the Marking Experiments, the Age and Growth 

 of Plaice, the Invertebrate Fauna, the Eggs of fishes collected during 

 last June, the Bottom Deposits, the experiments with small-meshed 

 nets covering the commercial trawl, and the Grimsby Trawlers' Records. 

 The materials on which these reports are based have been summarized, 

 and the chief conclusions of many of them mentioned, in previous 

 reports. Some others may be added here. 



Transplantation Experiments. — The reports on these experiments 

 take the form of a review of all the results of English experiments 

 carried out between 1904 and 1908. Thirteen of these experiments, 

 dealing with 3942 fish, consisted in the transference of plaice from the 

 coastal grounds of the North Sea to the southern parts of the Dogger 

 Bank. Half the plaice transplanted were between 20 and 23 cm. in 

 length on liberation ; from which it will be seen that for the purposes 

 of estimation of growth and percentage recaptured, and of the study of 

 migration, the majority of the experiments must have been closely 

 comparable. By the end of June, 1909, with which month the period 

 covered by the reports ends, nearly a thousand of the plaice had been 

 returned. 



The two most noteworthy features of the growth in length of the 

 plaice recovered were the undoubted growth which was found to have 

 occurred on the Bank during the winter months and the ample con- 

 firmation afibrded of the high estimates of a year's growth derived from 

 the first experiments of the series.* Thus the average growth of the 



• Garstang. Expts. iu Tiansplantatiou, etc. First Report, Southern Area. 



