174 JOURNAL, R.A.S. (CEYLON). [VOL. XVI. 



The Pearl Fishery of Japan. 



In the Bay of Agu, in the Province of Shima, Japan, 

 an extensive pearl fishery exists. The pearl oyster of this 

 region (M. Martensii) appears to be the most northerly 

 situated of the pearl -bearing species of Meleagrina, and it 

 lives under conditions which more nearly resemble those 

 which obtain on the oyster banks of Europe — where the true 

 oyster (Ostrea edulis) is cultivated — than those which sur- 

 round its own congeners in tropical seas. The Japanese pearl 

 oyster lives in quite shallow water, and is left exposed upon 

 the banks at low tide. This condition of things would seem 

 to present special facilities for artificial cultivation ; but, 

 unfortunately, on this very account large numbers of the 

 shells perish of the cold in winter. Professor Mitsukuri, of 

 the Imperial University, Tokyo, has inaugurated an elaborate 

 system of cultivation, which gives promise of good results. 

 One of the principal features of the scheme is the collection 

 of the "spat" in shallow water, and its transference to 

 comparatively deep water — 6 to 7 fathoms — where the tem- 

 perature is more equable. Here the young oysters are 

 constantly watched and protected against the attacks of 

 predacious foes. I hope to be able to obtain further parti- 

 culars of this interesting experiment as the work proceeds. 

 At present fuller information is not available. 



Artificial cultivation after the Chinese method has also 

 been attempted in Japan ; but, so far, only hemispherical 

 pearls, whose bulbs are attached to the shell, have been 

 produced. Japanese pearls are not commonly seen in the 

 markets of London and Paris, probably because there is 

 always a demand for them at home. 



The Pearl Fisheries of California and Panama. 

 In the time of the Jesuit Missionaries the Central American 

 pearl fisheries were actively carried on, and produced great 

 wealth to those engaged in the industry. But they after- 

 wards fell into decay, and for many years the banks were 

 thought to have been exhausted. More recently, however, 



