Abstract
In judging the age of a fish, it has been customary to resort to the frequency of those rings among many individuals of the fish which are intuitively chosen as annual ring from the rings observed on the scale, the vertebra or otolith. Consequently, this has necessarily led to results not free from personal errors.
The author, now recording the frequency of any rings detectable at all on the scale for uniformly sized individuals of a fish to be examined, tries to estaflish a standard procedure for objectively estimating the age of the fish. By means of this new design it was revealed that with Euthyopteroma virgatum (H.) the chance of ring formation is provided in two seasons every year [while most individuals of this fish form (only two) rings per year.].
