Abstract
In 1938, MATSUBARA made a statistical observation based upon 44 specimens belonging to the genus Synaphobranchus taken in Japanese waters, and suggested that the group of the genus represents a single species, Synaphobranchus pinnatus (GRONOW). In that study, however, he did not touch upon the vertebral counts.
On the other hand, BRUUN (1937) and NORMAN and TREWAVAS (1939) did really sound and comprehensive research in the taxonomy of this group.BRUUN classified the larval form of this group into several species besed upon the differences in counts of myotomes. NORMAN and TREWAVAS reexamined all the types of this group either directly or indirectly and classified them into i. number of species mainly based upon the differences in counts of vertebrae and the general forms of the scales on sides of body.
We have had of late an opportunity to examine 60 specimens of this group taken in various parts of Japan and have found that the specimens used in his previous study by MATSUBARA (1938) agree well with S. kaupii JOHNSON and that our present specimens can be distinguished into three species, S. kaupii JOHNSON, S. affinis GÜNTHER and S. brevido-rsalis GÜNTHER respectively, mainly by the differences in counts of vertebrae and general forms of both scales and upper pharyngeal teeth.
