262 THE GREAT BARRIER REEF. 



For the three succeeding 3'ears the produce and value of the same fisheries are given as follows ; 



In the year 1887 (cited as furnishing the latest statistics immediately available), the total 

 number of oysters taken from the French fisheries is quoted at 375,000,000, showing that the 

 magnificent record of the year 1876 has been beaten. 



Among the evidence brought forward in the Sydney letters, with the view of depreciating the 

 efficacy of the French system, much stress is laid upon the circumstance that, some twenty years 

 ago, the Hon. Thomas Holt, recognising the value and capabilities of that system, undertook, 

 at an expense of some _^io,ooo though unfortunately without success, the construction of exten- 

 sive culture ponds, or " claires," at George's River, New South Wales, for the cultivation of 

 oysters on the same principle. The causes that led to the failure reported, however, were not 

 attributable to the system, but to the fact that a species of oyster differing essentially in form, 

 habits, and methods of propagation, from the European type, was experimented with. Having 

 recently availed himself of the opportunity of inspecting the extensive "claires" constrticted by 

 Mr. Holt, the author is of the opinion that they are altogether unsuited for the culture of the 

 Queensland and New South Wales commercial oyster, Ostrca glomcrata, which was the subject 

 of experiment. On the other hand, they would in all probability prove highly suitable for that 

 special fattening process of Ostrca edulis, for which alone these claires are utilised in France. 

 These structures, in France, take the form of shallow ponds of from twelve to eighteen inches 

 in depth, and are so connected by means of sluices with the sea, that fresh streams of salt 

 water obtain access to them only at spring-tides ; the water throughout the intervening periods 

 remaining completely stagnant. It is through the culture of the French oyster under these special 

 conditions that that green coloration of the oyster's tissues is acquired which commands for it so 

 high a price in the Paris market, the colour being due to the character of its food, which consists 

 almost exclusively of microscopic plants known as diatoms, and the spores of confervoid algse. 

 This special claire system of oyster culture is in no way suited to the Queensland bivalve. 



Oyster culture on the French system, on the other hand, in so far as it consists of providing 

 supplementary material, or apparatus, for the catchment of the redundant supplies of spat, is 

 undoubtedly worthy the attention of all oyster-growers. Whether this material takes the simplest 

 form of the returned parent shells or cultch, or of tree-branches or fascines, or of cemented tiles or 

 boards, but one result has to be accomplished ; and it resolves itself to a question, simply, as to 

 which of these can be most economically or profitably employed on the areas under cultivation. 

 In this direction, it will be found that different descriptions of oyster-ground yield the best results 

 in association with diverse descriptions of collectors. On those beds and banks which are more 



