抄録
For different kind of fish the time of scale ring formation is not uniquely determined according to the circumstance through which they have grown up; it varies usually with every species. Even with one species, moreover, peculiarities in geographic region where they live, their age and degree of maturation have influences upon the season in which the ring is shaped.
Out of an examination made for a number of different species of fish having just passed through a coldest season it was inferred that at most 35% of them had such a ring as situated closely to scale periphery, suggesting that ring formation in winter is rather a rare case.
The scale ring seems to be formed in general in an early period of generative maturation and/or in a spawning-time of the fish.
