CHAPTER XI 



SCIENTIFIC RESEARCH AND THE SEA FISHERIES 



FOR centuries biologists have investigated the fauna and 

 flora of the sea, and since fish form the most important 

 constituent of the fauna we have a lengthy series of treatises 

 on the subject commencing with Aristotle (384-322 B.C.). Until 

 comparatively recently, however, monographs on marine fishes 

 were for the most part systematic, i.e. the characteristics by which 

 the various species might be distinguished from each other were 

 fully described, whereas the biology, i.e. the life history and habits 

 was neglected. Modem ichthyological research may be said to 

 date from the investigations of G. O. Sars, a Professor at the Uni- 

 versity of Christiania. To him is due, in 1864, the credit of the 

 discovery of the pelagic nature of the eggs of marine food fishes 

 (with a few notable exceptions). He found the ova of the cod and 

 other members of the cod family in the sea in the vicinity of the 

 Lofoten Islands. These eggs were small, round, transparent, jelly- 

 like bodies floating in the upper layers of sea water. Sars collected 

 them by means of a fine meshed net of silk or muslin, transferred 

 them into jars of sea water, where he was successful in keeping 

 them till the young fish hatched out. He also obtained ripe eggs 

 from the body of the adult female, and proved it was possible to 

 fertilise them artificially by milt taken from the male of the same 

 species. This remarkable discovery of Sars has since been con- 

 firmed and extended to the eggs of other valuable marine food 

 fishes. In fact, it may be stated that, broadly speaking, with the 

 notable exception of the herring, the eggs oi all our important food 

 fishes have buoyant pelagic eggs of the nature above indicated. 

 The eggs of the herring, on the contrary, are heavier than salt water, 

 and consequently sink to the bottom, where they undergo their 

 development. The extreme importance of this solitary discovery 

 may be realised when it is stated that twenty years afterwards it 

 was freely stated by many witnesses (fishermen and others) l^tore 

 the Royal Commission of 1885 that the eggs of marine food fashes 

 were to be found on the bottom of the sea, where they were subject 

 to extensive destruction by the trawl. Since these eggs were in 



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