334 The Commercial Products of the Sea. 



upon the branches ; two or three months later, they have 

 grown into soft round leaves, apparently similar to stems, 

 and several inches in length. These stems now rapidly 

 flatten out at the ends into broad leaves, which are taken 

 off every alternate day all through the winter, until the end 

 of March. At this period they become hard, unfit for use, 

 and fall off during the summer months. The quality of this 

 seaweed depends very much on the weather, and is best 

 when frequent rains and falls of snow have rendered the 

 shallow water more or less brackish. Too large a propor- 

 tion of sweet water is unfavourable to the growth of the 

 plant. A century or two ago it was gathered in large 

 quantities at the mouth of the Sumidagawa, near 

 Asakusa in Tokio ; but as the river carried down with 

 it a large quantity of gravel, its mouth advanced more 

 and more into the sea, and the water near Asakusa be- 

 coming too fresh, the plant disappeared. Owing to this 

 circumstance, the above-described mode of cultivation was 

 instituted ; the weed, however, has preserved its former 

 name of Asakusa nori. The branches of Quercus serrata, on 

 which the weed grows, are said to answer their purpose 

 during three years ; after that time, however, the bark 

 comes off, and the weed does not grow any more. 



Large shipments of cumboo or seaweed are annually 

 made from the port of Hakodate, to the value of about 

 ;i6,ooo. It is divided into three sorts the best coming 

 from Shimani and Yokadsu, the second quantity from 

 Akish, and the third from Kusudu. This article appears 

 in the Hakodate market throughout the whole year, with 

 the exception of the winter months ; and has two crops, 

 the first from September to December, and the other from 

 May to August. There is a good business also carried on 

 with seaweed to China from Nagasaki and Kanagawa, 



