222 



On the Rate of Growth of some Sea Pishes, and the 

 Age and Size at which they begin to Breed. 



By 

 J. T. Cnnninghani, m.A. 



The following paper is to be regarded as the sequel of that 

 published in the preceding number of this Journal^ on the rate of 

 growth and distribution of young marine fishes. I am still con- 

 tinuing inquiries of this character, and have now to record the 

 additional results obtained up to the end of March, 1892. I have 

 also described and criticised some of the results of other workers in 

 the same field. 



Gadus morrhua, the Ood. 



Continuous observations on the growth of marine fishes in 

 captivity have very seldom been made up to the present time. 

 Isolated observations are scattered here and there in Day^s British 

 Fishes, and Marion, in the Annales du Musee de Marseille of 1891, 

 has described how he reared the alevins of a species of mullet and 

 of Sargus till they were nearly a year old, but none of these experi- 

 ments were caiTied on with the object or with the result of ascer- 

 taining definitely the most important facts in the life-history of the 

 species. So far as I have discovered, continuous observations on 

 the growth of fish from the earliest stage almost to the adult 

 condition have only once been attempted before I carried out my 

 own upon flounders, namely, those of Dannevig upon cod. Dannevig's 

 results are described in his Reports upon the Fish Hatchery of 

 Flodevig, published by the Selskah for de Norske Fiskeriers 

 FremTYie,* and an account of them by Professor Cossar Ewart is to 

 be found in the Fifth Report of the Fishery Board for Scotland for 

 the year 1886. In one respect Dannevig^s experiment was superior 



* See Aarsberefcning, 1886, of Selskabet for de Norske Fiskeriers Frerame, Bergen ; 

 Beretning oin Flodevigeus Udklaskningsaustalts Virksoinhed i Femaaret, 1883 — 1888, 

 Arendal, 1889. 



