458 NATURAL SCIENCE. Jone, 
The pearl and pearl-shell fisheries are of great importance. As 
an export from Queensland, pearl shell has ranked for the last five or 
six years as the sixth or eighth most important substance. These 
fisheries are confined to the tropical area of the Queensland coast, and 
are intimately associated with the Barrier-reef. The mother-of-pearl 
shell is collected in water from 7 to 20 fathoms deep. Formerly it 
was found in areas practically exposed at low tides. Queensland 
derives a revenue from licenses required to be taken by boats, 
ships, and sailing masters, and from a small royalty on the amount 
of shell collected. 
Owing to considerable depletion of the more readily accessible 
fishing grounds, the average weight of shells has decreased. Large 
shells weighing six to eight pounds a pair are still to be got, but the 
more ordinary yield averages two-and-a-half pounds the pair. A 
protecting Act of Parliament now prohibits the taking of shell with a 
less diameter than six inches across the pearl lining or “ nacre.” 
The specific form of the Queensland waters is Meleagvina 
margaretifeva. Actual pearls of large size and fine quality are found, 
but enormous numbers of the shells contain worthless forms. 
Some experiments have been made in the artificial production of 
pearls, not according to the Chinese methods by introducing metallic 
or other foreign bodies into the mouth to be covered by a pearly coat, 
but the process has as yet only a speculative value. 
The author made a series of experiments with a view of finding 
methods of removing young shells from the breeding grounds to 
shallow water where they might grow to maturity in undisturbed 
security. He found that young living examples with a diameter of 
no more than a quarter of an inch might be safely removed by cutting 
through the byssus. When the animal was placed in an aquarium 
the remains of the byssus were ejected and a new byssus secreted, 
and in most cases a secure reattachment formed in the new habitat. 
The animals havea slight power of locomotion, but nothing com- 
parable with the active movements of pectens. 
In removing larger shells from deep water for relaying in shallow 
water, several methods were tried. Some were placed in shady places 
on deck and had sea-water thrown over them at intervals. For 
others, the American method (employed in the case of oysters)— 
muzzling the shells with wire to prevent the opening of the valves— 
failed to secure the retention of the fluids in the shell, as they escaped 
by the byssus groove. The mortality in these two cases was very 
great, but entirely successful results were obtained when the shells 
were kept in tubs of water, the water of which was changed every 
few hours, and the actual shells immersed in basket-work frames in 
the sea at night. 
When these shells were laid down in frames in shallow water 
where the water was pure and the currents strong, remarkably 
healthy and active growth took place. It may indeed be said that 
