抄録
The Gold-fish fries which were hatched at the same time, from the same parent fish, grow up in different grade. It seems to be not only due to the heredity but also the fact whether they were given enough feed soon after they were hatched. Four groups were put into experiment; that is, the one was fed immediately after they were hatched, and the other threes were begun to feed on the fifth day, on the tenth and on the fifteenth after they were hatched respectively. They were fed in the pots for 153 days and their growth, survival and decolaration of the body were examined. The result is as follows.
1. The fluctuation of growth of the newly hatched fry of Gold-fish seems to be increased, when the beginning time of artificial feeding is delayed. In consequence, the appearance of special larged-sized or small-sized fry might be caused more by the different power of individuals aquired under the enviroment of their habitat rather than that of their own heredity.
2. The more the beginning time of artificial feeding is delayed, the less (in number) the fries survive and the more the phenomenon of decoloration of their body is slowly presented.
