Muscle proteins of the Japanese crucian carp were analized by the cellulose-acetate electrophoresis.The muscle protein patterns usually composed of four components were divided into three types by the percentage of each component to total amount of protein.Type I, having more than 20% component 1, is represented by two forms, Kinbuna, Carassius buergeri buergeri and Nigorobuna, Carassius buergeri grandoculis.This type is also divided into three subtypes, A, AB, and B, by three phenotypic protein patterns controlled by two codominant alleles.A remarkable difference between Kinbuna and Nigorobuna was found in the occurrence of Type 1B, which is dominant in Kinbuna, not in Nigorobuna.Type II characterized by having more than 70 component 2 is represented by “Ginbuna, ”Carassius langsdorfii.Type III possessing components 2 and 3, each of which is nearly equal and about 40 %, is represented by “Gengorobuna, ”Carassius cuvieri.The muscle protein electrophoretic patterns are proved to be useful to trace the speciation of the crucian carp.

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The spinal curvature and the vertebral counts were investigated in fifteen races of the goldfish (Carassius carassius auratus), as compared with five forms of the crucian carps.On the basis of the spinal curvature, the examined fishes were roughly classified into the following three groups. The first group with Kin-buna type curvature, which includes all forms of the crucian carps is characterized by having the abdominal vertebrae always located above the base line and the majority of the caudal vertebrae are situated bellow the line (the degree of spinal curvature is generally small in its value).The second group with Wakin type curvature, which includes five races of the goldfish is closely related to the first group, but the degree of spinal curvature is comparatively large in its value.The third group with Ryukin type curvature, which includes other ten races of the goldfish is characterized by the vertebral column always situated above the base line (the degree of spinal curvature shows comparatively larger value).The total vertebral counts show relatively high values in the crucian carps, while the counts are somewhat reduced in most of the goldfish. And also it is presumed that there exists a negative correlation between the degree of spinal curvature and the total number of vertebrae.

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The brief history of the Paracanthopterygii is reviewed.Some relevant problems are discussed with the view that these aspects have not received sufficient attention or that their interpretations are equivocal with present data.No new information is presented.The group-concept is accepted as a reasonable hypothesis on which to base further testing.Nevertheless, the present constituents, in their sum, seem to be an unnatural group.The polymixioids and indostomoids are rejected as part of the overall group.The relationship of the gobiesocoids, gobioids and ophidioids, as part of the Paracanthopterygii, are seen as tentative hypotheses either lacking strong evidence or with unexplained evidence against inclusion.The Ophidioidei are removed from the Gadiformes.Two other groups, the notothenioids and callionymoids, should also be studied.
Basic objections center on the acceptance of present myological and neurological evidence as being more than preliminary.Fundamental understanding of possible trends in these characters has not reached the level that is present in osteology.The effects of mode of life and plasticity of the myological and neurological systems are not yet known in detail.

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The oogenesis of the Japanese sea bass, Lateolabrax japonicus, one of the common marine teleosts in Japanese coast, is fundamentally similar to those of the other bony fishes described so far.However, in this fish, oogenensis is marked by the characteristic pattern of distribution of the yolk vesicles and the rather shorter period needed for the maturation of the oocyte in the yolk vesicle stage into the ripe ovum.Though sufficient explanations for these characteristic patterns of maturation process are not available, the shorter period required for oogenesis seems to be closely related to the mode of their life.The follicular cells play an important role in the supply of nutrition for the growing oocyte and phagocytic function for the atretic oocyte.In this respect, the follicular cells seem to function like the seminiferous epithelial cells of the testis, intensely suggesting that their origins are homologous genetically.It was also ascertained that the seasonal change of the values of gonad index reflects somewhat precisely the fish maturity.Both a microscopical observation of ovary and the data of gonad index indicate that in Wakasa Bay spawning occurs from late December to middle of January, mostly in early January.The biological minimum size of the female is about 350 mm in body length which corresponds to the size of two or three year age group.

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Stomach contents were examined in 106 individuals of Salvelinus leucomaenis collected in the mountain tributary of the Seki-gawa River near the foot of Mt.My Oka during the period from April through December, 1964.From autumn to spring, stomachs mainly contained aquatic and benthic animals, whereas the land insects were dominant in mid-May through August.Most of these insects were nest-builders and dwellers in and near the river banks, but not good flying ones. Among the aquatic insects taken, the case-bearing caddis worms occupy the highest percentage. This evidence seems to be correlated with the morphological devices of mouth and feeding behavior and accessibility rather than with the preference for food.The fact that the mature fish takes the diet continuously even in the breeding season might be one of the causal factors of no post-spawning death in the land-locked (non-migratory) form.

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Skeletal elements of Brachypleura novaezeelandiae Günther of the family Citharidae collected from the South China Sea were examined.This species has been known as a transitional form between the primitive genus Psettodes and typical members of flatfishes.Osteological features of B.novaezeelandiae were compared with those of two citharids, Citharoides macrolepidotus Hubbs and Lepidoblepharon ophthalmolepis Weber.The definition of the family Citharidae which includes Brachypleura was revised.

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The so-called gizzard in mugilid fishes is a pyloric portion of the stomach, which is thickly muscularized, and adapted to the detritus feeding.To clarify the critical stage in the development from larval to juvenile, which is often found corresponding to the change of feeding habit as well as the development of digestive organs, the menada mullet, Liza haematocheila (Temminck and Schlegel), was tested for the understanding of the problem.Samples, selected in series from the batch hatched and cultured artificially in laboratory, were studied anatomically and histologically, with special attention to the development of gizzard.
The differentiation of the organs in digestive system can be categorized into 10 (I-X) stages, each characterized by the type of intestinal convolution taking place in the larvae to juveniles, 3-30 mm in total length or during about 2 months after hatching.The development of the gizzard and other organs in the system-lver, gall-bladder, pancreas, stomach, pharyngeal pad, etc.are clearly distinguished by the 10 stages as to their development and differentiation. The blind sac shows its anticipative body at the junction between oesophagus and intestine when larvae grow to 6.2 mm in length and intestinal convolution falling on IV to V stages, and gastric gland appears beneath the epithelium of anticipative blind sac.Upon the establishment of the blind sac, the gizzard begins to develop at pyloric portion in the larvae 9.0 mm long with intestinal convolution of V stage, and the organ establishes in VI stage, and they change habit from pelagic to benthic swimming during the development.With the growth in size of the gizzard, the blind sac dwindles gradually until the former fully establishes its shape in the juveniles 20 mm long.The occurence of gastric gland in cardiac portion and blind sac of stomach (instead of pyloric portion) was confirmed in Liza haematocheila and also in other mugilids, Liza carinata (Valensiennes) and Mugil cephalus Linnaeus.
It is well known that the L.haematocheila brings out extremey high yield of seedling (fry) under artificial breeding as compared with other fishes such as Seriola quinqueradiata Temminck and Schlegel, Pagrus major (Temminck and Schlegel), and Plecoglossus altivelis Temminck and Schlegel, which are also bred under nearly the same process for the mullet. This may be explained by the reason that the larvae of the mullet in early stages are already provided with digestive function of high fidelity which is derived from early differentiation of the gastric gland, early growth of the strong pharyngeal organ, and faster development of the gizzard.

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Sponsored by International Biological.Programme, a survey was made in 1970 and 1971 on Tasek Bera region, central Malaysia for the biological productivity (terrestrial and aquatic). The survey concurrently included limnological study of the Lake Bera covering fish biology and general hydrobiology, which was conducted especially in February, March-June and October-November, 1971.The lake, a“black water”swamp ecologically, developes about 30 km along the River Bera, a tributary to the River Pahang pouring into South China Sea, and expands by inundations 0.5-5 km in its width over the wet marsh of rain forest (Fig.1).The bottom of the lake, sounding 1-2 m deep, is mostly vegetated by 3 types of emergent and submerged plants and only partly left open.The fish fauna of the lake was studied by the collection using several types of gears and was found to include 70 species in 45 genera (Table 1).The incidental collection of fishes in the waters adjacent to the lake contained another 59 species in 35 genera, which recorded up to data from the region the total of 105 species in 57 genera falling under 25 families.
The diel rhythm in the moving of fishes in the water was studied by setting 7 units of gill-net (Fig.1) which were hauled periodically for the checking of fishes caught.The study was conducted in 3 seasons as above.Assuming that the number of fishes gillnetted by unit gear indicates a relative activity in their moving, the 15 species in the total of 21 species encountered were divided into 2 groups.Fishes comprising 6 species are more active during daytime than in nighttime and the other represented by 9 species show the opposite activity, the former group categorized“diurnal” and the latter“nocturnal”in diel periodicity (Table 2).
On February 11 and 12, the same 7 units of gillnet were operated for 24 hours, and the catch was checked in every 2-hour interval, thus, producing the total of 861 fish represented by 21 species (Table 3).Among these, 6 species were diurnal, 9 species were nocturnal and the rest were not classified because of their small number in catch.Analyzing the data thus obtained, it is noted evident that the fish population if treated as a whole shows moving activity is twice a day, i.e., in twilight (16: 00-18: 00 hours) and in dawn (06: 00-08: 00 hours), and vesperal activity is nearly twice vigorous than the auroral.Collectively the population may be called crepuscular in moving activity.However, it is further noted that the mode of twicea-day activity differs between diurnal species (Fig.2) and nocturnal species (Fig.3) In diurnal species the activity falls closely on zero level during nighttime or between auroral and vesperal activities but it is held continuously during daytime although much less vigorously than in crepuscular periods, whereas, in nocturnal species the activity comes to standstill during daytime but it is kept continuously with some fluctuation during nighttime.It appears highly significant to find that the diurnal species move more actively during crepuscular period than the nocturnal species.
Stomach content was examined on 9 species collected in February, and the number of food organisms found in all the stomachs examined was counted.Six species among them, regardless of their diel activity, highly depend on insect larvae and pupae dominated by chironomid and ephemeropterid, which will indicates the insect larvae occupying an important food resource for the fishes in the water.Also shown by 4 species (Figs.2, 3) that the diel activity of the fishes is interacted with their feeding behavior, since these two activities well correspond with each other whether in diurnal or nocturnal species.In this connection it was discussed that the crepuscular (bimodal) activity shown by fishes or predators does not correspond to the emergence of the aquatic insects or preys which takes place only once astart-page=295

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The structure of the free neuromasts was studied with 13 species ot-teleost larvae.In general, the neuromasts were onion-like in shape, and consisted of pear-like receptor cells and pillar-shaped supporting cells.The rod-like cupula extending out from the apical edge of each neuromast showed PAS positive reaction.
Species differences were recognized in the period of initial formation of cupulae on the free neuromasts.In larvae of Lateolabrax japonicus, Acanthopagrus schlegeli, Kareius bicoloratus, Blennius yatabei, Tridentiger obscurus, Tridentiger trigonocephalus and Fugu niphobles, the freeneuromasts were provided with well-developed cupulae at hatching.On the other hand, in larvae of Hypomesus transpacificus nipponensis, Tribolodon hakonensis, Zacco platypus, Cyprinus carpio, Carassius auratus, and Oryzias latipes, the cupulae on the free neuromasts became visible one day or a few days after hatching.

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The maturation of female Japanese eel (Anguilla japonica in sea-run stage) and the artificial acceleration of their maturity were studied, using 19 specimens obtained at the mouth of River Shimanto, Kochi Pref., from September through October, 1971.Majority of oocytes of the eel, about 0.3 mm in diameter, were at the oil drop stage characterized by numerous oil drops distributed throughout the cytoplasm and fine yolk globules occurring in the peripheral area of the cytoplasm.Some oocytes, larger than 0.4 mm in diameter, however, had numerous yolk globules in the outerhalf of the cytoplasm, and were at the primary yolk stage.The largest oocyte examind here reached to 0.59 mm in diameter.Specimens treated with dipropionic acid estradiol (follicular hormone) and“synahorin”from November 22, 1971 to the end of March, 1972 had eggs at much advanced stage.One specimen had some apparently mature eggs which were larger than 0.95 mm in diameter, and at the tertiary yolk stage.

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