Interspecific relationships were investigated in 23 species of the cyprinid genus Puntius on the basis of the features of infraorbital bones, pharyngeal bones and their teeth, lateral folds and barbels on the snout, and color pattern.Six phyletic groups were recognized in these fishes.In general, species belonging to the same group have overlapped or about equal geographic distributions.Between Southeast Asian and Indo-Ceylonese groups a more or less distinct gap is found in the degree of development of lateral folds and barbels. The results of this study indicate that Bleeker's (1863) division of Puntius into the subgenera Puntius, Barbodes and Capoeta is not acceptable from a phylogenetic viewpoint.

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Three forms of the Dolly Varden, Salvelinus malma, land-locked form (Miyabe char), river-resident form and sea-run form, were examined with special reference to their growth and development.The growth rate of the Miyabe char was closely similar in early stages of growth to that of the river-resident form, but a remarkable difference of body size appeared from two years of age, when the former descended into the lake and grew rapidly thereafter.The Miyabe char attained maturity at a later and more advanced growth stage than the river-resident form.The most striking difference was that a remark-able inflection corresponding to the fork length of the smolt was recognized in the relative growth line of the sea-run form, but the Miyabe char and river-resident form did not show this inflection in the growth line.The Miyabe char, therefore, might have more neotenous body form and size in relation to its precocity than the anadromous one.The process of land-locking and the subsequent evolution of the Miyabe char might be similar to that of kokanee,
Oncorhynchus nerka, land-locked in lakes.

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Discordipinna griessingeri is described as a new genus and species of gobiid fish from the tropical Pacific, Indian Ocean, and the Red Sea.The genus is unique among gobiids in the forward placement of the dorsal fin over the end of the head and the associated alterations of the anterior vertebrae.

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Population structure, reproductive behavior and protogynous sex inversion of the angelfish Centropyge interruptus was studied in the waters of Miyake-jima, Japan.A single male dominates a harem of from one to four females, with the size of the harem being dependent upon the nature of the substrate.Females are controlled by aggressive herding by the single male.Six action patterns associated with maintenance of dominance by the male and with courtship are described.These include (1) rushing, (2) circling, (3) soaring, (4) mutual soaring, (5) nuzzling, and (6) spawning.Spawning usually takes place almost every day at approximately sunset during the period from May to October.
Removal of the male resulted in sex change by the ranking female.Histological ex-amination of the gonads confirmed field observations of protogynous sex inversion.The histology of the gonads of females, males and intermediate individuals is described.

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The Stichaeid genus Dictyosoma has so far been regarded as represented by a single species, D.burgeri.Critical examination of specimens referred to Dictyosoma revealed that this genus includes two species.D.rubrimaculata is described as new.This species is distinguished from its congener, D.burgeri, by the lateral line structure, counts for dorsal and anal fin rays and vertebrae and coloration.It was also detected that there are two geographic forms in D.burgeri.D.rubrimaculata occurs along the Japanese coasts of the Pacific and theSea of Japan, and is sympatric in its range with both of the two forms of D.burgeri.In the Pacific coast the two species show more or less clear isolation in their habitat preference;D.rubrimaculata inhabits rocky and weedy shores, while D.burgeri commonly inhabits poorly vegetated, sandy to rocky intertidal zones.Ecological isolation is not yet investigated in the Sea of Japan.Morphological and ecological observations suggest that D.rubrimaculata is more primitive than D.burgeri.

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A lepidological study on sea-run specimens of Oncorhynchus rhodurus obtained from the Nagara River and Ise Bay was performed in comparison with the biwamasu (a lacustrine form of O.rhodurus), the amago (a fluviatile form of O.rhodurus), the sakuramasu (a sea-run form of O.masou) and the yamame (a fluviatile form of O.masou).The scale of the smolt of sea-run specimens of O.rhodurus has an unequal growth in width and length, and also in apical and basal areas, shifting the relative position of the focus.In the biwamasu, ridges are formed in the apical area as well as the basal area, but in the sakuramasu, many ridges are semicircular, disappearing in the apical area.In sea-run specimens of O.rhodurus, some ridges disappear in the apical margin in almost all specimens.So that, apical ridge formation in sea-run specimens of O.rhodurus is considered to be in an inter-mediate condition between the biwamasu and the sakuramasu.In the amago, apical ridge formation resembles that of sea-run specimens of O.rhodurus, and in the yamame, it resembles that of the sakuramasu.

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Specimens of char with atypical color patterns were collected in the Shiratama River, tributary to the Nikko River, and in the Aizawa River, tributary to the Mogami River, both located in Yamagata Prefecture, northern Honshu, Japan.These specimens exhibited marked color variations, ranging from individuals with no light spots nor parr marks to those having vermicular, arabesque or zigzag patterns.According to the shape and distri-bution of the body markings, these specimens were classified into four types.Comparison of electrophoresis of cyanmetho Hb, as well as that of morphometric characters, of these atypical-pattern specimens with Salvelinus leucomaenis possessing ordinary color patterns showed no difference between them.These atypical-pattern specimens are therefore con-sidered to be color variants of S.leucomaenis, rather than hybrids between S.leucomaenis and other salmonid species.

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[in Japanese]

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[in Japanese]

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A sea-run specimen of Oncorhynchus rhodurus Jordan et McGregor was collected by a set net on May 8, 1977 on the Echizen Coast in Fukui Prefecture, facing the Japan Sea.Counts and measurements on this specimen are presented.It is presumed that this salmonid fish is derived from the amago O.rhodurus which was previously introduced artificially into the upper streams of Kuzuryu River tributaries or the Kuroko River in Fukui Prefecture.

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