2o8 THE GREAT BARRIER REEF. 



shell of the Indian and Pacific Oceans. Two prominent varieties, the one with a golden edge, 

 and the other having a uniform silvery or nacreous consistence throughout, are pretty evenly 

 intermingled, and do not, so far as the author's investigations have extended, present any marked 

 distinctions in the aspect or structure of the contained animal. The last-named variet\-, having 

 the nacreous lining, or true mother-of-pearl, pure and uniform throughout, is the more valuable, as 

 it cuts up to greater advantage. This same large white mother-of-pearl shell, or "White Shell," 

 as it is commercially designated, is occasionally on the Western Australian coast suffused with an 

 exquisitely delicate pale pink hue, while in the neighbourhood of Manilla and the South Sea 

 Islands the same species is frequently highly iridescent in association with a distinct golden sheen. 

 For commercial purposes, these abnormal variations are held in little repute, the purest white 

 shell invariably commanding the highest price A smaller black-lipped shell, rarely exceeding a 

 diameter of six or seven inches, with a weight of from i lb. to if lb. per pair, is common throughout 

 the Barrier district, but has not hitherto been turned to much commercial utility in Queensland. 

 This smaller species is, however, extensively fished for on the West Australian seaboard and 

 in the Indian and China seas, both on account of the marketable value of the shell and 

 the number and good quality of the pearls that it produces. In West Australia, the range of 

 this smaller black-lipped species extends as far south as Champion Bay, or a latitude of 29 degrees, 

 closely parallel with that of Brisbane and Moreton Bay. The corresponding Queensland type, 

 although most abundant farther north, is also indigenous to Moreton Bay ; and it is a matter 

 worthy of investigation whether this species might not be profitably collected, or even culti- 

 vated, for the sake of both its shell and pearls, throughout the Queensland seaboard. In the 

 wholesale market, this black-bordered mother-of-pearl shell is sold under the title of " Black- 

 edged," while in the retail or shell-cutting trade it is technically known as " Black Scotch," 

 and it therein commands a price of from £b^ to £']o per ton. 



A black-edged mother-of-pearl shell of almost identical shape and texture, but of very 

 much larger size than the Australian variety, is procured from the Polynesian islands generally, 

 and is known in the London market as " Tahiti Black." Its weight and dimensions are 

 often equal to those of the largest white. At occasional intervals, when a craze for black 

 or "mother-of-pearl" buttons has temporarily prevailed, this black shell has obtained an 

 even higher price than the best white. 



Through the courtesy of Messrs. H. Kiver & Co., one of the leading mother-of- 

 pearl shell mercantile houses, the author is enabled to reproduce one of that firm's most 

 recently issued reports of the shell that has passed through their hands. This report will 

 place the reader en rapport with the extensive trade that is transacted in mother-of-pearl shell. 

 It also indicates the system of classification that is adopted by the brokers, and the 

 relative position occupied by the Queensland shell in the London market, with relation to 

 that derived from other localities. Some of the trade terms employed in this report 



