u 



'274 BULLETIN OF THE BUREAU OF FISHERIES. 



fish, if necessary, to the length of :-!i» centimeters in the tirst year, and to 50 centi- 

 meters in two years. They are put on the market any time after the second year. 



Carp culture is carried out extensively in parts of Japan other than Tokyo, 

 especially in mountainous parts where sea fishes ran be transported only with diffi- 

 culty, and the industry is spreading more and more every year into all parts. One 

 interesting reason for this is found in the circumstance that wet paddy fields in which 

 rice is grown, and which occupy such a large portion of the cultivated area in Japan, 

 are found in many low-lying districts to be excellent for the raising of the carp. 

 The rice plant not only does not receive any serious injury from it, hut is benefited 

 because many insects are devoured by the carp. In the prefectures of Nagano 

 (province Shinano) and of Gifu (province Mino) carp culture has progressed very far 

 in this way. In Nagano, which is also noted for silk-worm raising, abundant food 

 for the carp is found in the pupa' of the silkworm, taken out of the cocoons when 

 these are reeled. This gives a had flavor to the meat of the carp, however, which 

 has therefore to undergo the process of purifying culture before it suits the taste of 

 the fastidious. In one village in Shinano (Sakurai Mura) the agricultural society 

 which represents the whole village undertakes to utilize 250 acres of paddy fields in 

 the village in this way and annually raises 25,000,000 young tish to be sold and raised 

 in the eastern provinces. In Mino, in the prefecture of Gifu, these communistic 

 enterprises have gone further. There land is partitioned off into what are called 

 ••embankment areas "— that is. areas inclosed within a circle of embankments against 

 the overflowing of large rivers. In one of these areas, called the Takasu embank- 

 ment area, all the villages within it, with a total of 75,000 acres of paddy fields. 

 have combined in the business of carp culture, and although the enterprise is still in 

 its infancy, succeeded in realizing 48,000 yen in L902. The example is being fol- 

 lowed in other areas. 



THE EEL. 



Anguilla japonica Temminck and Sehlegel. 



As has already been mentioned, in the piscicultural establishments in Fukagawa, 

 Tokyo, and in the neighborhood of Maisaka, province Totomi, the snapping turtle, 

 the carp, the eel, and the gray mullet ("ina"), especially the last three, are often 

 cultivated together in the same ponds. That the eel finds itself one of this trio is 

 due largely to the efforts of Mr. Hattori, the expert pisciculturist. He experi- 

 mented long as to the best way to make eel culture a paying business, and succeeded 

 so well that this is now the most profitable of the three fishes named. 



The process is as follows: In April little eels that are brought to the Tokyo market 

 from all the districts around the capital (Tokyo. Ibaraki, Chiba, Kanagawa, etc.) are 

 bought. They are probably in the second year of their growth and are about 15 to 25 

 centimeters in length and weigh J-i to 20 grams. They are put in the same ponds with 

 the carp and the gray mullet in varying ratios, although the total weight of the fishes 

 put in should not exceed (ilo grams per 1 tsubo (6 feet square). They are fed abun- 

 dantly with the same kinds of food as the carp— that is. crushed molluscs, earthworms, 

 etc. It is a wonderful sight when they are led. They come crowding from all parts 

 of the pond to the spot where food is given them, and literally thousands are seen 



