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necessity for closer observation of the habits, food, and life 

 history of the fish. As regards habits and food much valu- 

 able information can be gained from fishermen, but allowance 

 must be made for inaccuracy. The results of their observa- 

 tions are not noted down at the time they are made, and too 

 much reliance is apt to be placed on memory — ^in most cases 

 an unsafe guide. Moreover, such observations must neces- 

 sarily be imperfect. The desirability for close and accurate 

 investigation cannot, in fact, b© too strongly urged, and such 

 investigation can only be carried out by trained men. Practi- 

 cally nothing is known, so far as I can ascertain, of the life 

 liistory of our most valuable fish. An important step in the 

 direction of obtaining such knowledge has, however, been 

 made by the N.S.W. Government in the appointment of Mr. 

 H. C. Dannevig as an expert inspector to superintend all 

 fisheries investigations, and, in addition, to initiate a system 

 of fish hatching, and to the publication by the N.S.W. Govern- 

 ment of papers and lectures by that gentleman I am largely 

 indebted for facts mentioned in this address. In a lecture 

 delivered before the Amateur Fishermen's Association in 

 Sydney on ''Marine Fisheries and Fish Culture,'' Mr. Danne- 

 vig points out that owing to recent careful enquiry in Eui'ope 

 and America, much light has been thrown on the reproduc- 

 tion of fish, and much that was till recently obscure is now 

 understood. The reproduction takes place in various ways. 

 A few fish are viviparous and give birth to from a few dozen 

 to about one hundred of their young, and these are born un- 

 der such conditions as to lead to the survival of the majority. 

 A second and more common method of reproduction is by 

 means of what are called demersal eggs, these being of com- 

 paratively lai'ge size and hardy. They are deposited either 

 in large bunches or clusters, usually hidden away in undisr 

 turbed places, or separately on seaweed or some other article 

 on the sea bottom. The larvae from these eggs are fairly 

 well developed, but still are more liable to destruction than 

 those w^iich have been born alive in a morel mature condition.. 

 Consequently the number produced by the female fish is from 

 a few thousand to forty or fifty thousand. This method of 

 reproduction is observed chiefly among fresh water fish, but it 

 has been noticed also in the case of a few sea fish. A third 

 and still more common method is by means of pelagic or 

 floating eggs, which are deposited a few at a time near the 

 coast, and which, being carried hither and thither, some to 

 the shore and some to mid-ocean, are subject to enormous 

 destruction. To counterbalance this the female fish produces 

 egga in great numbers from 250,000 to as many as twenty mil- 



