CULTIVATION OF MARINE ANIMALS IN JAPAN 709 



The eggs take eight to nine days to hatch. The young for the first 

 few days are given the yolk of hen's eggs, boiled. Food is usually 

 given them on shallow earthenware plates, slung by three strings 

 from a bamboo pole for the youngest, these plates being kept at the 

 depth of a little over one inch below the surface of the water. For the 

 next two or three weeks the young are given various kinds of fresh- 

 water Copepoda. These the goldfish-breeders prepare beforehand in 

 a separate pond, for they have the knack of producing these water- 

 fleas in any quantity they need at any time they like. After Copepoda 

 succeeds the ordinary food of the goldfish, such as fresh-water earth- 

 worms, boiled cracked wheat, etc. It is essential for the growth and 

 health of the fish that they be kept as warm as possible; hence, the 

 shallow earthenware dishes from which they are fed are kept at first 

 - that is, when the fish are first hatched, and, therefore, in the hot 

 season - - only a little over an inch below the surface of the water. 

 With the growth of the young and the approach of the colder weather 

 they are gradually put down lower and lower, until in the winter they 

 are down nearly ten inches, such a depth being naturally warmer than 

 nearer the very surface of the water. 



Among the young fish all sorts and conditions of the body and 

 the fins are found, that is, all forms intermediate between those 

 closely resembling the normal crucian carp with a long, slender body, 

 the unsplit tail and anal fins, etc., and those which are extremely 

 modified, as shown in the varietal types described above. If a lot of 

 young contains a large percentage of those with the unsplit tail, it 

 is considered, from the commercial standpoint, a failure, for these 

 latter are only a fraction of the split-tailed in price. In some ex- 

 periments I have tried, it was found that, in selecting for breeding, 

 the adults which have the split anal fin give, on the whole, better 

 results than those with a single anal. It is needless to say that all 

 undesirable ones are early eliminated. 



All the young just hatched are dark in color, the bright colors 

 coming only later. A great deal of experience and skill is needed in 

 making the goldfish change its color from black to red. If a person 

 who is not an expert tries his hand at raising a lot of young goldfish, 

 he will find to his sorrow that the fish remain black and do not assume 

 bright colors, while those which may be from the very same lot of 

 eggs, but have been under the care of a professional breeder, may have 

 all donned the beautiful hues. The essential points to be attended to 

 in bringing about this change seem to be (1) that the young fish should 

 be given plenty of food, (2) that they should be exposed to the sun's 

 rays and be kept as warm as possible, and (3) that the water of the 

 pond in which the young are kept should be changed occasionally, 

 although sudden transfer from warm to cold water in the middle of 

 the day is to be avoided. The change of color begins in about sixty to 



