INTRODUCTORY. 3 



It is also conducting scientific investigations with a view of 

 increasing the supply of bait, and determining the movements and 

 life-history of food fishes, and the conditions which are favourable 

 or the reverse to their increase. 



The principal inland fisheries of the country are under the 

 control of district Fishery Boards, but these, with one or two 

 brilliant exceptions, have hitherto held that the principal duties 

 required of them were to police their district. If the History of 

 Howietoun persuade district Fishery Boards that their sphere of 

 usefulness is wider than they have hitherto held, I shall be amply 

 rewarded. 



But whether we take our sea fisheries or our inland district 

 Fishery Boards, no country in the world can show the same intelli- 

 gent care of their fisheries, or the same substantial development 

 within the last twenty years, and we have every reason to expect 

 that the next twenty years will see the still greater advance. 



The experiments at Howietoun have demonstrated that the 

 first point to ascertain before any improvement of the fisheries can 

 be successfully undertaken, is at what period in the life-history 

 of the fish the greatest loss occurs. 



That loss does occur may be inferred from the large number of 

 eggs most fish produce, a number so large that, were it not for 

 the loss, a very few seasons would suffice to overstock the waters. 

 There are three periods at which this loss may be conceived to 

 occur. At the time of extrusion impregnation may be deficient. 

 This probably causes a great proportion of the loss in large-ovaed 

 SalmonidcB, but does not seem likely to be a source of loss with 

 fish which congregate in shoals for spawning purposes, as the 

 herring, especially when the gelatinous nature of the envelope of 

 the ovum is taken into consideration. 



The period of incubation of the ovum forms the second period 

 at which loss may be conceived to occur. With the large ova of 

 salmon, the proportion of loss here is probably greater than at the 

 first period, the duration of incubation extending over several 

 months ; while, in the case of herring, especially when spawning 

 in summer, the duration of this period is so short, that in spite of 



