708 OCEANOGRAPHY 



The goldfish is very common in Japan, and more or less reared in 

 all parts, but the main centres of cultivation are Tokyo, Osaka, and 

 Koriyama (a small town near Nara, where almost every household 

 engages in this business). Each of these places has its own peculiar- 

 ities in the method of raising, but the differences are, on the whole, in 

 minor details only. In Tokyo goldfish-breeders are all located in low- 

 lying parts of the city, where ponds, a sine qua non of this business, 

 can be easily made. 



One establishment is very much like another, the principal differ- 

 ences being in the number and size of ponds. There is always a num- 

 ber of shallow ponds, sometimes to the number of ten or more. 

 Shallow dishes, slung by three strings from bamboo poles stuck in 

 the muddy bottom of the pond, are the dishes in which food is 

 given to the goldfish. Besides these shallow ponds there is always 

 a large number of shallow cement basins of various sizes, some as 

 small as three feet by three, others as large as twelve feet by twelve, 

 with intermediate sizes of all sorts. They are very shallow, be- 

 ing not more than a few inches deep, can be easily drained or filled, 

 and can be shaded or exposed to the sun at will. A visit to such 

 an establishment would delight the hearts of not only children, but 

 grown-up persons who love bright colors and graceful forms, for the 

 ponds are full of brilliantly colored fish of all ages and sizes. Here 

 are huge fourth-year "wakin," there graceful second-year "ryukin," 

 off there fine "ranchu." Ornamental little carps, little tortoises, and 

 tiny fish called "medaka" (Aplocheilus latipes) are also generally 

 found in the goldfish-breeders' establishments. 



The process of rearing goldfish is in its main outline as follows: 

 Large goldfish that are three or four years old, with good forms and 

 healthy in every respect, are carefully selected for the purpose of 

 breeding. This takes place any time between the last part of March 

 and the middle of June, the usual time being in April and May. At 

 this season the color of the fish becomes more brilliant than ever, and 

 small, low warts that can barely be felt with one's finger are said to be 

 produced on the opercula of the male. Both sexes crowd together, 

 causing great commotion in ponds in which they are kept. Plenty of 

 a water- weed ("kingyomo," or "matsumo," Ceratophyllum demersum 

 Linnaeus), or bundles of fine roots of the willow-tree, are placed in the 

 pond, and on them the goldfish lay their eggs. It is an interesting 

 fact that goldfish-breeders are able to control, within a certain limit, 

 the time of deposition of eggs. If the fish are given plenty of food 

 beforehand, and then the water of the pond in which they are kept is 

 renewed, or if they are placed in another pond, they will deposit eggs 

 in a day or two. On the contrary, if they are underfed and kept in the 

 same stagnant water, they will desist from depositing eggs, sometimes 

 altogether. 



