Iviii 



Thirty-first Annual Report 



as is also their relation to the migrations of the fishes themselves, and 

 to the movements of the floating organisms upon which young fishes 

 of most species, and certain fishes at all stages, as the herring, chiefly 

 • subsist. An investigation was therefore undertaken, and is now 

 proceeding, to ascertain as completely as possible the course, direction, 

 and rate of the currents along the East Coast and throughout the 

 North Sea, the results of which will be afterwards considered in 

 connection with the hydrographic observations. For this purpose a 

 large number of sealed bottles, suitably weighted and containing 

 numbered cards for identification, have been thrown into the sea from 

 the " Goldseeker " at various places along the coast. Of 2920 drift- 

 bottles of this kind which have been put into the sea, 717, or over 24 

 per cent., have been returned, partly from our own coast and largely 

 from the Continent, more especially from Norway, some of them 

 having been found as far as the North Cape, and even farther east in 

 Barents Sea and the Murman coast. 



Traiding for Herrings. 



Investigations on the action of the new herring- trawl, particularly 

 with respect to the capture of immature herrings and white-fish, were 

 made by the " G-oldseeker " at the Dogger Bank and neighbourhood, 

 and also in localities in the inshore waters where small herrings were 

 known to abound in greater or less numbers. Experiments have also 

 been initiated with similar cod-ends, but with different meshes from 

 those used by the commercial vessels, with the object of determining 

 the most satisfactory mesh that might be employed. These investi- 

 gations are being continued, and it is believed that the results, 

 combined with those obtained on board the vessels when trawling for 

 herrings for commercial purposes, will go far to show how the 

 question can best be dealt with internationally. 



Experiments on the Relation hetween the Size of the Mesh of Trawl 

 Nets and the Fishes Captured. 



As mentioned in last Report, investigations are being carried on to 

 determine as precisely as possible the relation between the size of 

 the mesh of trawl nets and the numbers and sizes of the fishes taken, 

 the method adopted being to use cod-ends of different mesh, with a 

 loose bag of fine-meshed netting outside, in which the fishes which 

 escape through the apertures of the cod-end of the trawl are retained, 

 so that the catches in the two nets may be compared. A report on 

 these experiments is in course of preparation. 



Observations on the Eggs and Larvm 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-net, numerous collections were made by special 

 nets of the floating eggs and the young of the food fishes at different 

 seasons and at various localities. By this means information is 

 obtained as to the spawning season and spawning regions of the 

 fishes, and as to the distribution of the eggs. Observations of this 

 kind were mad(^ all along the East Coast and eastwards at intervals 



