2 o THE NA TURE-STUD Y RE J 'IE W \ , : -January, 1906 



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 experiments 

 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 gold-fish change its color from black to red. If a person 

 who is not an expert tries his hand ai raising a lot of young gold-fish 

 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 the 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 occasion- 

 ally, 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 eighty days from the time of hatching, and by the middle of 

 August the fish should all have lost the dark pigment and acquired 

 bright colors. I am told a curious fact that the fish which change 

 their color earliest are apt to be white or variegated white and red, 

 while those that change later are apt to be uniformly red. What can 

 be the significance of such a fact ? I am also told that by the middle 

 of August of the second year, all the individuals, however obstinate, 

 change their color. It is worth while determining whether, even if 

 the young are left to themselves and not given the care which they 

 receive at a breeder's, they will change color by the summer of the 

 second year. 



White is commercially worthless and is ruthlessly weeded out. It is 

 also said that to improve the brightness of the color, the fish should 

 be somewhat underfed — that is, should be given about 90 per cent 

 of the ordinary feed. In Koriyama they have the trick of bleaching 

 out white spots in the red, by applying some mixture. The result, 

 I think, is not worth much. 



I have by no means exhausted the subject of the gold-fish ; in fact, 

 I doubt whether anyone can write all the minute details of the art of 



