On a Japanese Flying-fish and its Juvenile of the Genus Prognichthys BREDER

A flyingfish of the genus Prognichthys BREDER and its juvenile form obtained from southern coast of Japan are treated on this paper. Their characters are listed on the tables 1 to 6. Present species differs from P. gibbifrons, P. tringa and Danichthys mainly in the following points. Namely, the first ray of anal is originating vertically below the second to fourth ray of dorsal, and the number of anal rays is I or 2 fewer than or equal to that of dorsal; further, it has 47 or 48 vertebra instead of 42 or 43 in P. gibbifrons and 45 or 46 in Danichthys. The juvenile agrees with those of Atlantic Prognichthys and Danichthys described and figured by Breder (1938) and Bruun (1935) in having peculierly differenciated pectoral, broad ventral, and highblack dorsal as in Parexocoeius,but is different from them in having a pair of barbel at symphysis. the ovarian egg is apparently demersal, with 48-66 tendrils evenly distributed over the surface, alld 1.5 to 1.6 mm in diameter