BIOLOGICAL SClliNCl- AM) 



INDUSTRY. 



TilL LLAKJJXG 



.1 tcicawinu-iitsoii Dr. Jiimcson's Pii/ycr fiiihlialu-d in '■ Know i.i-:i)c;i:," \'()/. .V.V.Vl' ^Xovcmhcr. l'JI2i. p. 121 . 



hv T. II. IIAV.NES. 



Tin-; adiniralilc .summary tliat Dr. Jameson has 

 draw n up of the biological and economic aspects of 

 the pearl and pearl-shell industries may be regarded 

 as the sole publication of the kind existent, and its 

 value is self-evident. It comes at an opportune 

 moment when a Federal Royal Commission is sitting 

 in .\ustralia to inquire into the pearl-shelling industry, 

 and the State Legislatures of Western .\ustralia are 

 discussing a new Pearling Hill that is designed to 

 confer security of tenure upon would-be cultivators, 

 and to establish a fund for promoting the culture of 

 pearl-shell. The motive power behind the Commis- 

 sion and the new Bill is the determination to turn 

 tropical .Vustralia into a white man's countr\-. and 

 the pearling industry, which is the only occupation 

 which employs any substantial number of people, 

 into a white man's industry. It is, therefore, of the 

 highest importance that the information available for 

 the Royal Commission should be of a sound character, 

 so that erroneous ideas and false hopes maN' not be 

 perpetuated, and I think that through the good 

 offices of " Kno\vi,i-:dge " these aims will be 

 secured. 



Dr. Jameson has cleared the air on several 

 important points, viz. : — 



The distinction between pearls and "blisters" 

 and the delusion that exists that any progress has 

 been made in the artifical production of pearls. 



The futility of endeavouring to breed pearl-oysters 

 without an enclosure. 



The difference between true cultivation by breed- 

 ing from parent stock and semi-cultivation by the 

 transi)lantation of natural-grown young shells to 

 private ground. 



The difficulty of distinguishing between the young 

 of the true pearl-shell and the false " reef" or 

 '■ bastard " variety. 



In my "statement of evidence" wliicii 1 li.i\< 

 sent out to the Ro\al Commission, I have dealt 

 with these subjects very much in the same way as 

 Dr. Jameson has done, and I have also referred to 

 the friendly controversy which exists between him 

 and myself regarding the 1910-11 experiment at the 

 Montebello Islands. Dr. Jameson disputes my 

 claim to have raised young pearl-shells {Margaiitifcra 

 maxima) from the parent stock in my pond, and I 

 am glad of the ready permission of the Editors of 

 " KN()\VLi:i)t;i-; " to defend my case, and to rejieat 

 the arguments which I laid last jear before Mr. 



II. C. Dannevig (the Federal Director of Fisheries 

 in Australia) and have now sent to the Com- 

 missioners. 



1. In the first place let me say that the amount of 

 water flowing automatically into the pond, on the 

 flood, varies very much according to the state of the 

 tide, rising springs, falling springs and neaps. The 

 result is the main thing. The temperature and 

 salinity remain normal and the parent-stock thrives 

 in a marked manner. So also do young reef-shells_ 



2. Trial specimens opened for exainination showed 

 signs of spatting early in November, the gonads 

 exuding ova or milt when severed by the knife. 

 The bulk of the parent-stock was opened at the end 

 of March, and the exudation was more profuse then 

 than in November and December, but shells from 

 the open sea, especially from deep water had by 

 that time ceased to show any exudation when cut. 



.5. I commenced operations by closing the pond 

 on November the 21st. On November the 29th the 

 water inside suddenly became very blue and did not 

 reco\er its normal appearance until December the 

 Jrd. No such change had ever been noticed before. 

 On December the 9th young oysters of the size of 

 pinheads were found on some of the collectors 

 near to the breeding-stock trays. On December the 

 29th another batch appeared, and a still more 

 copious batch on January the 3rd, and doubtless others 

 occurred which were not noticed. These voung 

 oysters in shape would pass either for pearl-shells or 

 bastard-shells and the byssus attachment was visible 

 with the glass. They varied in number on each stone 

 collector — up to fifty or sixty. Every effort was 

 made to rear them, some in the pond and some 

 slung in cages in the open tideway : but without 

 success, as they quickly began to disappear, and 

 within a fortnight or so each batch had completelv 

 \anished. There were no fragments of shell left and 

 they must deliberately have detached themselves 

 and probabl\- fell into the film of mud or sediment 

 at the bottom and were smothered or de\oured h\ 

 bottom vermin. On February the 6th, a hurricane 

 blew my house into the sea and I lost ever\thing in 

 it, including the mounted specimens of these \oung 

 oysters. No further notes were taken as to what 

 was going on in the pond, but numerous other 

 batches of young shells probably came into existence 

 and disappeared in like manner. 



4. Here and there about the pond I found an odd 

 shell on the collectors, of much larger growth, w idely 



