EEPORT OF THE COUNCIL. 489 



ill the Journal. One, by Mr. (>. E. Bullen, deals with the food of the 

 mackerel, and suggests a correlation between the abundance of mackerel 

 -on the fishing grounds off the Cornish coast in May, and the amount 

 of Copepod plankton, upon which the fish feed, present in the water 

 at the time. The second paper, by Dr. Allen, attempts to carry the 

 question a step further, and shows some evidence for thinking that 

 the abundance of mackerel in May varies with the amount of sunshine 

 in the earlier months of the year (February and March). It is 

 .suggested that the amount of sunshine influences the growth of 

 diatoms and other plant life, which in its turn influences the Copepod 

 plankton upon which the mackerel feed. 



Mr. E. W. Nelson has again been engaged, in association with 

 Dr. Allen, in experiments on the cultivation of marine plankton 

 •diatoms and the rearing of pelagic larvte. A report on this work is 

 now in preparation. 



Mr. A. E. Hefford has been occupied in studying the reproduction of 

 teleostean fishes in the neighbourhood of Plymouth by means of obser- 

 vations of the gonads of mature fishes, and of the eggs and larvae 

 taken in tow-nettings, and in a modified form of the Petersen young- 

 fish trawl. 



Eecords have been kept of the pelagic eggs collected at regular 

 intervals during the early months of the present year. The eggs, with 

 few exceptions, were kept alive in the Laboratory, and observations 

 were made on the developing embryos and the early larval stages. 

 An outstanding feature of the investigation is the preponderance in 

 abundance, though not in numljer of species, of the eggs of unmarket- 

 able fishes over those of marketable forms, those of Motdla and of 

 Callionymus lyra being particularly abundant and of continuous 

 occurrence. 



The commencement of spawning for most of the species observed 

 appears to have been earlier this year than usual. 



The International Fishery Investigations. 



The following is a summary of the work done, and of the conclusions 

 arrived at by the scientific staff working under the direction of the 

 Council. 



Section I— NORTH SEA WORK. 

 A. WOEK OF THE S.S. "HUXLEY." 



From June 1st, 1908, to the end of May, 1909, the Huxley made 

 nine voyages, in the course of which 193 hauls of the commercial trawl 

 were made, together with 116 hauls of various smaller nets and gear. 

 The total number of voyages made by the Hvxley from the commence- 



