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Part III. — Seventh Annual Report 



II. REPORT ON THE SPAWNING OF THE BRITISH MARINE 

 FOOD-FISHES. By J. C. Ewart, M.D., Regius Professor of 

 Natural History, University of Edinburgh ; and T. Wemyss Fulton, 

 M.B. 



Introductory. 



Hitherto our knowledge of the spawning of the British marine fishes 

 lias been imperfect, and has been chiefly derived from the empirical 

 observations of fishermen and the more or less isolated inquiries of 

 marine zoologists. A reference to works on Ichthyology, therefore, not 

 unnaturally shows that very divergent opinions have been held both 

 as to the place and the time of spawning of even the commoner kinds of 

 marine fishes. This has arisen largely from the fact that man}'' observers 

 have formed conclusions frequently from too few specimens, or from the 

 statements of fishermen and others ; but, no doubt, in many cases from 

 the observations having been made at different parts of the coast. A 

 perusal of the evidence led before the various Commissions appointed to 

 inquire into fishery questions in recent years will make it evident that, 

 as a rule, the statement of those engaged in fishing cannot be trusted in 

 these matters, for a somewhat remarkable opposition of views is brought 

 out even in the same districts. 



A very general opinion, and one prevalent not only among fishermen 

 but among many who have written on fisheries, is that most marine 

 fishes at maturity migrate to the inshore waters and there deposit their 

 spawn. This idea appears to be based partly on the fact that fishermen 

 occasionally obtain quantities of the spawn of molluscs and other 

 invertebrates, of the lump-sucker, herring, and of small or unimportant 

 littoral forms, on their lines and nets close inshore ; and partly because 

 very young fishes are found in great abundance, especially during the hot 

 months of the year, in the shallow waters around the shore. The result 

 of our observations, however, go to show that the deposition of the spawn 

 of the food-fishes close inshore on the East Coast is exceptional, for it 

 appears that at the approach of the spawning time most of the food-fishes 

 congregate in shoals in the waters lying at some distance from the coast, 

 and there the ova are cast forth and fertilised. 



It is now well known from the observations of Sars, Hensen, Raffaele 

 and others that the spawn of almost all the marine food-fishes float, 

 in a dispersed and isolated condition, at or near the surface of the sea. 

 So far as observations have been made this is true of all the marine food- 

 fishes, with the exception of the herring, and of certain small or unim- 

 portant littoral forms whose ova are deposited at the bottom more or less 

 close to the shore. 



The investigations, the results of which are embodied in this paper, 

 have been carried on for a year, more especially in the Firth of Forth, 

 St Andrews Bay, and the adjoining waters. In addition, a large number 

 of fish from inshore and offshore grounds in the Moray Firth have been 

 examined, and a considerable number from other districts on the East 

 Coast of Scotland. Altogether, nearly 23,000 fish have been examined, 

 comprising the following species : — plaice, lemon soles, turbot, brill, 

 halibut, long rough dabs, common dabs, flounder, witch soles (P. 

 c?jnoglossus), sail fluke or merry sole (Arnoglossus megastoma), little sole 

 (Solea lutea), various species of skates and rays, cod, ling, tusk, hake, 

 haddock, whiting, gurnard, dragonet, saithe, lythe, catfish, angler, lump- 

 sucker, weever (Trachinus draco), cobbler (Cottus scorpius), brassie 

 (Gadus luscus) and herring. Comparatively few specimens of the rarer 



