The present paper, the fifth of t he series of the pelagic fish eggs from Japanese waters, contains the figures and descriptions of 5 species belonging to the suborders Callionymina and Ophidiina. Callionymina. The egg and larval development of Callionymidae No. 1-3 are known from Japanese waters. These eggs are globular in shape, measuring 0.64-0.73 mm in diameter, lacking the oil globule. The egg membrane is somewhat thick and with hexagonal mesh structure, measuring 0.014-0.025 mm in diameter of the mesh. The yolk is segmented and the perivitelline space narrow. The eggs of this group resemble some species belonging to the family Sauridae, but can be discriminated from the latter by the small egg size, segmented yolk, appearance of the xanthophores in the egg and the number of myotomes of the hatched larva (less than 23 against more than 52 in Sauridae). The newly hatched larvae are about 1.5 mm in total length, having the xanthophores on the body, yolk and marginal fin. The melanophores are seen on the dorsal median line of the body, and in some species they are also seen on the yolk as well as on the marginal fin. About 1 day after hatching, serration appears on the fringe of the marginal fin. Ophidiina. The egg and larval development of B rotula multibarbata Temminck et Schlegel and Carapidae No. 1 are already reported by Kamiya (1916, '22) from Japanese waters. Both species beget agglutinated pelagic eggs. The eggs are imbedded in gelatinous substance making small globular or ellipsoidal mass. The eggs of both species are slightly ellipsoidal in shape, with a long diameter of 0.8-1.1 mm, containing a single oil globule measuring 0.13--0.20 mm in diameter. The egg membrane is smooth, without any conspicuous structure, the yolk not segmented, the perivitelline space narrow. In the course of the egg development only the melanophores appear, and many granules also appear on the embryonal body, yolk and marginal fin. The oil globule of the newly hatched larva is situated in the anterior part of the yolk. The newly hatched larva of Carapidae No. 1 has a small knob-like structure on the dorsal median line a little posterior to the anus.