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The present paper, second series of the pelagic fish eggs from Japanese waters, chiefly deals with the descriptions of the egg and larval development of 24 species belonging to the orders or suborders Lamprida, Zeida, Mugilina, Scombrina, Carangina and Stromateina with notes on the matured eggs of 6 species also belonging to these systematic groups, in aid of future studies. As far as known, the eggs belonging to these systematic groups are spherical in form, the egg membrane smooth without any conspicuous structure, and the perivitelline space narrow. Lamprida. Only a s ingle species, Trachipterus sp. is known from southern waters of Japan. The egg is large, measuring 1.9-2.3 mm in diameter, lacking the oil globule, and its early developmental stages are quite similar to those of Fistularia petimba Lacepede. The yolk is not segmented. During the course of the egg development elongated dorsal and ventral fin rays appear. The number of elongated dorsal and ventral fins is 4 and 3 respectively, the longest dorsal fin ray is as long as two-thirds of the total length of the body and is provided with 5 swelled parts covered with melanophores. The appearance of the oral part of the larva closely resembles to that of the adult. The number of myotomes is 87. During the course of the egg and larval development only melanophores appear. Zeida. The matured egg of Zeus japonicus Cuvier et Valenciennes is already reported by Kamiya. The egg is large, measuring 1.9-2.0 mm in diameter, with a single yellow oil globule measuring 0.35 mm in diameter. The yolk is not segmented. Mugilina. Mugil cephalus Linne, Sphyraena pinguis Giinther and their related species arc known from Mediterranean Sea, Indian waters as well as from Japanese waters. The egg diameter of M. cephalus is 0.72-1.08 mm, with a single oil globule measuring 0.28-0.40 mm in diameter. The yolk is not segmented. As the specific gravity of the egg slightly surpasses that of the sea water, the spawned eggs gradually sink. During the course of the egg development many melanophores and xanthophores appear on the embryonal body, yolk surface and oil globule. The oil globule of the newly hatched larva is situated at the posterior part of the yolk. The egg diameter of S. pinguis and its related species is 0.69-0.82 mm, with a single oil globule measuring 0.18-0.21 mm in diameter. The yolk is roughly segmented. The melanophores and xanthophores appear on the embryonal body, yolk and oil globule during the course of the egg development. The oil globule of the newly hatched larva is situated at the anterior part of the yolk. Scombrina. Thunnus thynnus (Linne) , Parathunnus obesus (Lowe), Sarda orientalis (Temminck et Schlegel), Auxis sp., Scomber japonicus Houttuyn, S. tapeinocephalus Bleeker and unidentified species resembling to S. japonicus, Scomberomorus niphonius (Cuvier et Valenciennes), S. kuhlii (Cuvier et Valenciennes), S. commerson (Lacepede), Xiphias gladius Linne, Tetrapturus belone Rafinesque, Trichiurus lepturus Linne and Coryphaena hippurus Linne are known from Japanese waters and the warm seas of the world. The diameter o f these eggs ranges from 0.9 to 1.9 mm, most species having a single oil globule measuring 0.2-0.6 mm in diameter, but some have several or many oil globules. The yolk is not segmented in many species, but some have segmented yolk. In many species the melanophores and xnathophores appear on the embryonal body, yolk and oil globule, and sometimes on the marginal fin during the course of the egg and larval development. The oil globule of the newly hatched larva is situated at the posterior part of the yolk in many species, but in some species it is situated at the anterior part. As the vertebral number of the fish belonging to this group usually differ according to the family or genus, so, to identify the eggs of this group, the myotome number of the hatched larvae is important characteristic together with the mode of change of the pigmentation during the course of the larval development. Carangina Trachurus japonicus (Temminck et Schlegel) and clo s ely related 3 other species, Decapterus russellii (Ruppell), Seriola quinqueradiata (Temminck et Schlegel) and Leiognathus nuchalis (Temminck et Schlegel) are already known from Japanese as well as Indian waters. The egg of carangid fishes ranges 0.7-1.3 mm in diameter, with a single oil globule measuring 0.17-0.33 mm in diameter. The yolk is roughly segmented. During the course of the egg development many melanophores and xanthophores appear on the embryonal body, yolk and oil globule. The oil globule of the newly hatched larva is situated at the anterior part of the yolk and partly protruded from its surface. The number of myotomes of the hatched larva is 26-28, and the anus is situated near the middle of the body and its position does not change during the larval development. In the marginal fin only the xanthophores appear in most species, but in some species a few melanophores also appear. The egg diameter of L. nuchalis is 0.60-0.65 mm, with a single oil globule measuring 0.12-0.15 mm in diameter. The yolk is not segmented. Excepting the lack of pigment in the marginal fin, the pigmentation is similar to those of carangid fishes. The oil globule of the newly hatched larva is situated at the posterior part of the yolk. Stromateina. Labracogl o ssa argentiventris Peters and the matured egg of Psenopsis anomala (Temminck et Schlegel) are known from Japanese waters. The egg is 1.00-1.33 mm in diameter, with a single oil globule measuring 0.21-0.25 mm in diameter. The yolk of L. argentiventris is roughly segmented, but this is not the case in P. anomala. The hatched larva of L. argentiventris has many melanophores, without xanthophores, and the oil globule is situated at the posterior part of the yolk.