376 SHELLS. [CHar. XI. 
movement, and unable of itself to quit the place to 
which it is originally attached’, he demonstrated, not 
only that it possesses locomotive powers, but also that 
their exercise is indispensable to its ceconomy when 
obliged to search for food, or compelled to escape from 
local impurities. He showed that, for this purpose, it 
can sever its byssus, and re-form it at pleasure, so as to 
migrate and moor itself in favourable situations.? The 
establishment of this important fact may tend to solve 
the mystery of the occasional disappearances of the 
oyster; and if coupled with the further discovery that 
it is susceptible of translation from place to place, and 
even from salt to brackish water, it seems reasonable 
to expect that beds may be formed with advantage in 
positions suitable for its growth and protection. Thus, 
like the edible oyster of our own shores, the pearl-oyster 
may be brought within the domain of pisciculture, and 
banks may be created in suitable places, just as the 
southern shores of France are now being colonised with 
oysters, under the direction of M. Coste.? The operation 
of sowing the sea with pearl, should the experiment 
succeed, would be as gorgeous in reality, as it is grand 
in conception; and the wealth of Ceylon, in her “ trea- 
sures of the deep,” might eclipse the renown of her 
gems when she merited the title of the “Island of 
Rubies.” 
On my arrival at Aripo, the pearl-divers, under the 
orders of their Adapanaar, put to sea, and commenced 
1 Srsvart’s Pearl Fisheries of Calendar for 1858.— Appendix, 
Ceylon, p. 27; Corpriner’s Ceylon, p. 14. 
§e., vol. ii. p. 45. 8 Rapport de M. Costz, Pro- 
2 See Dr. Keraart’s Report on fesseur d’Embryogénie, &c., Paris, 
the Pearl Oyster in the Ceylon 1888, 
