A new species of the priacanthid.fish, Pristigenys multifasciata, is described based upon 8 specimens from the Ryukyu Islands.This is the second species of Pristigenys from the western Pacific, and characterized by 10 or more vertical dark red stripes and strong ctenoid scales.

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Extra ossicles found in the oral region of Bleekeria vaga are described and illustrated in detail.They are ossified cartilaginous parts of the ligaments or ligamentous structures connecting the following bones and membranes;posterior ends of the maxillary and premaxillary to the anterior end of the dentary;the maxillary to the coronoid process of the dentary;the maxillary to the vomer;articular process of the premaxillary to the maxillary;and the articular process of the premaxillary to the tip of the rostral cartilage.
Similar ossicles are also found in B.gilli and B.renniei.Corresponding cartilaginous structures in B.viridianguilla, Embolichthys mitsukurii, Ammodytes personatus, and A.hexapterus are not ossified.
Among the fishes of the family Ammodytidae, B.vaga and B.gilli seem to have the most protrusile mouth, and the presence of the ossicles seems to have to do with the marked protrusibility of the upper jaw.These ossicles ase also absent in fishes of the Hypoptychidae and Trichonotidae, to which the family Ammodytidae was once considered to be related.

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Pulsating contraction of peripheral ooplasm of the eggs of a cyprinodontoid fish, Oryzias latipes, was observed after alveolar breakdown upon fertilization.The contraction is initiated at the animal pole region in the vicinity of the fertilization cone and propagates toward the vegetal pole.The movement of ooplasmic inclusions and of carbon particles injected into the peripheral ooplasm was examined after insemination, and it was suggested that ooplasmic segregation is induced by contractions of the peripheral ooplasm.

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Technique for implantation of cannula into dorsal aorta of fish was applied successfully to the carp, Cyprinus carpio, with body weight ranging from 500 to 1, 000 g.Effects of anesthesia and surgical operation were also investigated with hematocrit value as a parameter.In the carp, it is unnecessary to secure the cannula with any kind of fixation.Implanted cannulae can be used for 10 days or more, and as far as hematocrit value is concerned, the fish should be allowed to rest for at least 2 days after being cannulated.A few hours after the operation, hematocrit value decreases drastically against the value measured at the time of operation and then gradually takes a stable level 2 days after the operation.Hematocrit value increases when the fish is anesthetized by immersion in a standing solution as well as by irrigation with an anesthetic solution.

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The anemonefish, Amphiprion xanthurus, was studied on the island of Miyakejima, Japan, from 1969 to 1972, with special interest in the problem of territory and aggression.General life history studies were also conducted in nature and in the aquarium.
Most populations consist of a pair of fish, but this is due to territorial restrictions imposed by the size of the sea anemone colony.A.xanthurus is not biologically monogamous.
Both male and female defend territories, but territorial behavior differs between sexes.Male territorial energies focus outward, in defense of the periphery of the territory, while female territories focus inward on the accessibility of male nesting holes.Female territories may be more than twice as large as male territories and may overlap the nesting holes of two or more males. Dominance seems to determine the location and size of female territories.Males are more aggressive than females in defense of nest holes against invaders.Reproductive success seems to be the primary reason for territoriality in both sexes.Males defend nesting sites throughout the year, probably due to restrictions on availability of nesting space dictated by the size of the sea anemone colony.Immatures and some low ranking adults do not defend territory.
Crowding in aquaria results in increased aggression and more obvious dominance patterns.Invariably, females are dominant over males in the aquarium and display a subtle dominance in natuie.
Both bottom organisms and plankton seem to be important food for adult anemonefish.During the breeding season nearly all the anemonefish in a colony may occasionally rise up above the anemones to feed on swarms of plankton.The frequency of courtship and agonistic displays at such times suggests some sort of social mixing function.Various crustaceans are a danger to the eggs at night, when nests are unguarded.
A.xanthurus is able to tolerate temperatures of 13°C or less, and goes into semi-hibernation in winter.Life expectancy is probably three to four years.
On Miyake, Cymbactis actinostoloides and rarely Stoichactis kenti are apparently the only sea anemones with which A.xanthurus has a symbiotic relationship.At night anemonefish hide deep within the rocks at the base of the anemone or rest in the tentacles of the anemone.

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Pear-shaped cells and“vesicle-rich cells”in the epithelium of pyloric caeca of the rainbow trout, Salmo gairdneri, were examined mainly with the electron microscope.
1.Pear-shaped cells are faced on the epithelial lumen of the pyrolic caecum and separated from the basement membrane of the epithelium.They are provided with a small number of microvilli on the apical surface and connected with the neighboring epithelial cells by the junctional complex.The most conspicuous features are the encasing of the endoplasm with a layer of the finely filamentous material (corresponding to the ectoplasm or cytoplasmic capsule) measuring from about 700 to 850 mic in thickness just beneath the plasma membrane, provided with several tens of the membrane-bound rodlets in the central region of the cells, and showing mitochondrian concentration in great numbers in the upper part of the cells.
In the basal portion of the pear-shaped cells there is an indistinct or almost absent region of the cytoplasmic capsule where there appear several cored vesicles 900-1000 Å, .in size, various profiles of the rough endoplasmic reticulum with very sparse ribosomes and glycogen granules.Most nuclei of the pear-shaped cells in longitudinal sections take a horse-shoe shape and are located eccentrically in the base.Golgi apparatus, contiguous to the nucleus, consists of lamellae, many vesicles and an occasional vacuole.Cisternae of the rough endoplasmic reticulum show various vacuolized profiles with very sparse ribosomes on their outer sides.
Each rodlet consists of an oval ampulla and a long process extending toward the apical region of the pear-shaped cell.The process is projected from the ampulla but never into the pyloric caecum lumen.An electron-opaque axis originating from the ampulla runs the central part of each process.A number of cored vesicles 900-1000Å.in size tend to concentrate around the boundary between the ectoplasm (or cytoplasmic capsule) and endoplasm in the mitochondria-concentrated area, and they seem to be formed in tubular profiles of the smooth endoplasmic reticulum.
2.Pear-shaped cells are neither parasitic cells such as Rhabdospora thelohani, nor a life cycle form of goblet cells, nor wandering cells such as granular leucocytes and lymphocytes.
3.Several cells of a new type were found by electron microscopy in the epithelium of the pyloric caecum, close to the pear-shaped cell or singly, and were named as a “vesicle-rich cell”.The majority of cisternae of the rough endoplasmic reticulum show various vesicular profiles with very sparse ribosomes and contain the moderately electron-opaque flocculent or finely granular material.Flattened cisternae of the smooth endoplasmic reticulum wind in various directions forming a double or triple lamella whose development is different from cell to cell, and they are located also in the cytoplasm of the infranuclear area near the basement membrane.Morphological findings characteristic of Golgi complex except for the above-mentioned winding lamellae, however, have not been found, and therefore it is difficult to determine whether the lamellae can be identified with the Golgi lamellae.

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Morphology of three forms of Oncorhynchus rhodurus Jordan and McGregor were studied.In comparison with the fluviatile form and the lacustrine form in Lake Biwa, characters of the sea-run form resemble those of the fluviatile form, and differ from those of the lacustrine form in Lake Biwa in number of pyloric caeca, transverse scales, ventral fin rays, and in crimson spots on lateral body (Figs.4-6, Table2).
The sea-run form shows the following characters: the body color is silvery;the tip of the dorsal fin is dipped with jet black;crimson spots are scattered on the lateral side (Fig.2).Its smolt shows following characters;the body color is silvery;parr marks have disappeared;scales are easily taken off;the tip of the dorsal fin is dipped with jet black;the posterior margin of the caudal fin is edged with jet black;crimson spots are scattered on the lateral side (Fig.2).

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Details of morphological changes in tunas kept in confinement, have rarely been reported.The present paper reports on deformities appearing on heads of 3 species of tunas kept in an aquarium up to 172 days: Sarda orientalis, 5 specimens 314-340 mm in fork length and kept for 1-56 days;Euthynnus affinis yaito, 11, 272-382 mm, 10-72 days;Thunnus thynnus, 4, 229-328 mm, 1 51 days.The water, in a nearly closed system, was led by an inlet-pipe into the tank at the rate of 100 l/min, and was accelerated by two airlifting pipes in the tank.A translucent acryl-resin plate was inserted along the wall to prevent injuries to the fishes (Fig.1).The fishes were initially fed with chopped raw meat of the horse mackerel followed by the meat of penaeid shrimp;the daily ratio was under 20% in weight of tunas.
The deformation appeared as a swelling of the skin in the head region excepting a triangular area posterior to the eye (Fig.3).The feature of the deformity showed specific differences but were similar among individuals of the same species.The swelling of the skin was especially prominent on the snout to nape, and on the branchiostegal membrane.The deformity appeared earlier in the period of confinement and with more prominent skin swelling in the order of Sarda, Euthynnus, and Thunnus (Fig.2).Macroanatomical observation revealed that the swelling of the skin was caused by thickening of the dermis accompanied by some development of lumps of the subcutaneous adipose tissue (Fig.4).
Often, the periosteum of the membrane bones near the ventral border grew rough, associated with the development of adipose tissue, which coagulated with the periosteum.Among factors leading to the deformity of head, the confined space in which specimens were kept was believed to be highly responsible, because it was experienced that the same species of the tuna kept in round tank (6 m in diameter;holding capacity 31 m³;surface area 25.5 m²) showed similar head deformation but in lesser extent during more extended periods.
Additional discussion is made on the author's experience and other information concerning ^{Engraulis japonica}, Scomber japonicus, Scomber scombrus, Coryphaena hippurus, Trachurus japonicus, Alectis cilialis, Seriola quinqueradiata, and Seriola purpurascens.All are neritic pelagic species and show similar deformation in head when kept under confinement.Feeding, vitamin difficiency, flowing of water, surface area of tank etc., also play important roles in morphological abnormalities of fishes reared in tanks.

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[in Japanese]

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Three female specimens of the eel pout, Enchelyopus eloncotus (Kner), were, caught frorn Kunbetsu beach, Nemuro, Hokkaido on Dec.16, 1059 and Jan.19, 1960.Those lish.44.5.45.1 and 51.8cm.in total length.had 183.102 and 349 individuals of the fetus in the ovarian cavities, rc hcetively.The fetuses measured 45 io 50mm and Initl ilte inflated abdomen.No yolk suhstancc was left in he abdominal cavity, but the cavity was filled with voluminous and empty e pansion or the posterior portion of the intestine.

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A specimen of the pink Salmon, Oncorhynchus gorbuscha (Walbuum), was caught at the lower Akka River: draining to the Pacific coast of the northern Honshu, Japan, on September 9, 1972,
The specimen wsa a mature male with black blotches on the buck and tail, and 357mm standard length Scales J the. specimen are small and 164 on the lateral line. Characters of this specimen are anal fin rays 16, gill-rakers 28 and pyloric caeca 108.These values are the range for the pink salmon Qm which were collected in Hokkaido and reported by Hikita (1962) as shown in Table 1.
Akka. River, the pink salmon.was caught, is situited about 70 km south of Oiirase River along the.Pacicific coast of Honshu.shu, Japan (Sato and Sato.1964).The return of the pink sailmon has not been previously reported from the rivers situated south of Oirase.River.Therefore, Akka River isat present soiuhertintost limit of the return of the pink salmon along the Parilic coast of lionshu, Japan.

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