Three specimens belonging to the zoarcid genus Melanostigma were collected from Sagami Bay and Suruga Bay, Japan.They are similar to but distinct from M.atlanticum, and are described as M.orientale.The new species is the first record of Melanostigma from northwestern Pacific Ocean.

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Aspects of the anatomy of Dinolestes lewini (Griffith, 1834) are discussed in relation to the erroneous conclusion that this fish is a member of the Apogonidae. The monotypic family Dinolestidae is recognized and relationships are suggested with the Centropomidae and Sciaenidae. Relationships are not supported for. the Pomatomidae and Sphyraenidae.

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The digestive organs of postlarvae in 13 teleost species chiefly reared in laboratory were compared with one another to make clear their developmental processes.Characters differentiated during postlarval stage are teeth on jaws, pharyngeal teeth, taste buds, hepatopancreas, goblet cells in intestinal epithelium, gastric gland, pyloric caeca, and others.The time when teeth on jaws and pharyngeal teeth are formed varies from species to species.In general the jaw teeth in the species with stomach differentiate and develop at about the time when the gastric gland differentiates, and the pharyngeal teeth appear earlier than the former except for the puffer.The development of the lower pharyngeal teeth in cyprinoids is followed by the enlargement of upper cornified portion, or the cornified pad.Taste buds, which have already differentiated during prelarval stage in many species with demersal eggs, are formed within a week after feeding in every species.Pancreatic tissues which have already dispersed at prelarval stage partly invade into the liver along the hepatic portal vein to form hepatopancreas during the middle period of the postlarval stage.
After the start of feeding two conspicuous features appear in the epithelium of the intestine.One is the appearance of many vacuoles in the antero-median part of intestine, and the other is acidophilic granules in the posterior part of intestine.The posterior constriction with valvular structure forms the border between the two parts of the intestine.Their histological features and relationships with feeding conditions carry conviction that they are both absorptive features, and the vacuoles are fat, and granules are protein absorbed.These points will be explained in detail in reports which will be published in the future.
Many larvae change their body forms, and their fins except the pectoral differentiate during the final period of postlarval stage, when the gastric gland appears in the mucosa of the stomach.At the first stage of the formation of the gland, cuboidal cells well stained with hematoxylin constitute glandular acinuses without ducts to lumen in the anterior part of stomach, and afterward vesicles with secretory granules increase to construct a few layers in the whole part of the stomach.This remarkable event is attended with appearance of teeth on jaws and goblet cells with PAS positive materials in the epithelium of the intestine.
The age when gastric gland differentiates varies from species to species, for example, 90 to 120 days after hatching in Plecoglossus altivelis, 25 days in Acanthopagrus schlegeli and 20 days in Pagrus major. But the time corresponds with length of larval stage, and the relative differentiation time, which is nearly three fourths of larval period, hardly varies from species to species.This fact indicates that the differentiation of the gastric gland is strongly related to the transition from larvae to juveniles, which require more developing digestive mechanisms preparing for new foods in a new habitat.
Pyloric caeca appear following the completion of gastric gland.They are formed through projection of the intestinal wall at the most anterior part, so that their epithelium is identical with that of intestine.At the period when pyloric caeca differentiate, fishes are at the transitional stage from larvae to juveniles.At this time body forms are regulated to approach basic forms of their adults, and all fins are completed.
The digestive system of postlarvae is stomachless in structure, and may be at the undif-ferentiated state in function.Therefore it may be speculated that larvae have characteristic digestive mechanisms different from those of adults.

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The maturation of the yellowtail, Seriola quinqueradiata Temminck and Schlegel, cultured in a narrow floating net set in some coastal areas of southern Japan, Kochi and Oita Prefectures, during one to six years has been studied to obtain the fundamental information on its breeding.In one year old fish, the ovaries have not yet enlarged, about 5 g or less in weight, with numerous immature eggs belonging to early peri-nucleolus stage, throughout the spawning season.Male, however, possesses ripe testes from April to the beginning of May, though not enlarged markedly.In 3 to 6 years old fish, the gonads are well enlarged, nearly reaching 400g to 500g in weight in April, but rapidly begin to reduce its weight and function from May, after the surface water temperature reached to about 19°C.Almost all males examined here enough ripen in natural condition, but females do not, bearing rather mature eggs developed primary or tertiary yolk stage in which the largest eggs grow up to 0.43 mm to 0.77 mm in diameter.In addition, there is a tendency that the ovaries are much heavier in wild fish than in cultured fish (Fig.4).

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The gobiid fish, Astrabe lactisella Jordan and Snyder, attaining to 50 mm in total length in adulthood, has seldom been collected from rocky tide pools of the middle and western Japan.
The planktonic larvae and juveniles of A. lactisella, measuring from 6.7 to 12.0 mm in total length, were collected with boat seine of minnow net, working to catch mainly the larvae of the anchovy at the coastal water of Suzaki, Kochi Pref. (33°22.7'N, 133°17.4'E), in 1954 and 1955.
The planktonic larvae and juveniles, ranging from 4.9 to 15.4 mm, were also collected with fish lamp in Nomo Bay near Nagasaki (32°35.3'N, 129°45.5'E) during 1969 to 1971.One of the juveniles, about 12 mm in total length, was fed with copepods and reared for seven days in a 40-liter plastic aquarium and grew up to a 13.8 mm young entering into the early bottom life, while the late planktonic juveniles, ranging from 12.0 to 15.4 mm in total length, came around fish lamp in the bay.
The characters of the planktonic larvae of the fish, being about 5 mm, are as follows.The body is compressed moderately and rather stocky in appearance.The head is rather compressed with large eyes.The anus opens in the posterior part of body.The rudiment of the swim bladder begins to appear.The myomeres are 29 (14+15) or 30 (14+16) in each individual.Melanophores appear on the side of body except the posterior part of the tail.The body color is blackish.
The number of the spines and rays of each fin is nearly complete in a 11.1mm planktonic juvenile as shown in the following fin formula: D.III-11;A.10;P₁ 25;P₂ 5.
The planktonic larvae and juveniles were collected in both coastal waters of Suzaki and Nomo during early February to early May.The spawning season of the present species is probably from late winter to early spring in these districts.

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[in Japanese]

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