In Tokyo the favorite articles for spawning beds are living water plants, particularly the milfoil 

 (Myriophyllum vcrticillatian) and the hornwort (Ceratophyllum demersum), but in Koriyama 

 preference appears to be given to roots of the willow {Salix). Several weeks before egg-laying 

 time the fine, matted roots of the willow are collected in large quantities, thoroughly washed, then 

 boiled to sterilize them, and finally dried. 



The usual procedure, when spawning is imminent, as shown by the behavior of the fish and 

 the temperature of the water, is to transfer the fish to the spawning pond, the sexes being about 

 equally represented and the number depending on the size of the pond. The water plants or the 

 bundles of willow roots are placed in this pond, and on these the eggs are soon deposited. 



The common practice at Tokyo, in the case of the ranchu, for example, is to hold the ripening 

 fish in concrete basins. A small cultivator might have only three pairs of fish in a pond, while 

 an extensive cultivator might have twenty-five pairs. It is considered unnecessary to change the 

 water, and the principal attention the fish require is to be amply fed for about ten days before 

 spawning, the preferred food at this time being worms and mosquito larvae. As the ej«perienced 

 cultivator can usually tell when the eggs will be laid, the water in the spawning pond is renewed 

 the previous day, the milfoil is introduced, and the brood fish are removed thereto. For three or 

 four pairs of fish a pond or basin with an area of ten or twelve feet is sufficiently large, while for 

 twenty-five pairs the pond should be forty to forty-five feet in area. Then, should the atmospheric 

 conditions be suitable — a rise in temperature or a warm rain — the fish will spawn the next morning. 



When cultivated after the Tokyo method, the brood fish of the ryukin variety are kept in 

 mud ponds and are permitted to spawn in the same pond in which they have wintered. The ripening 

 and deposition of their eggs are encouragd by giving a plentiful supply of food, and the growth 



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