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OCEANOGRAPHY 



for this purpose and has been cut up into lots and leased to differ- 

 ent persons. Put this together with the fact that hills around here 

 are cultivated to the very top, and it would be difficult to go be- 

 yond this in the utilization of land and water. Hiroshima has per- 

 haps gone ahead of most places in Japan in this respect. 



FIG. 8. Ground-plan of a " toya." Collectors bearing well-grown oysters are 

 indicated by the black spots within the two circles of branching collectors. 



A rather interesting and simple system of oyster-culture has been 

 developed within the last twenty years at the mouth of the Sumin- 

 ouye River, in Ariake Bay, in the prefecture of Saga, Kiushiu. It- 

 seems that people here were in the habit of collecting all the natural 

 oysters they could and of preserving larger ones among them for a 

 little while on the bottom of the Suminouye River to be sent later to 

 Nagasaki for sale. For some reason, in 1884 those thus preserved were 

 left through the winter and it was discovered that by next year they had 

 grown to a large size. This fact was not lost on the sagacious people 

 thereabouts, of whom Mr. Murata, an enthusiastic culturist, seems 

 to have been the head and soul. From this beginning the industry 

 was developed so that 18,330 bushels of oysters, valued at 21,181 yen, 

 were produced in 1897, and the output has no doubt increased since. 

 The method is as follows: Young oysters about an inch or more in 

 length are collected constantly from July till March of the next year 

 from stonewalls, old shells, etc. All these are placed on oyster-beds in 

 the river-mouth, and, as these small ones may be choked by being 



