The pomacentrid fish genus Chromis is represented in Japan and Taiwan by the following20species: C.albomaculata Kamohara, C.alleni sp.nov., C.analis (Cuvier), C.atripectoralis Welander et Schultz (often confused with C.caerulea), C.atripes Fowler et Bean, C.caerulea Cuvier, C.chrysura (Bliss) (C.lepidostethicus (Fowler), C.westalli (Whitley) and C.isharae (Schmidt) are junior synonyms), C.elerae Fowler et Bean (recorded for the first time from Taiwan;not yet known from Japanese waters);C.flavomaculata Kamohara (C.kennensis (Whitley) is a junior synonym), C.fumea (Tanaka) (described as a Pomacentrus, here revealed as a Chromis;C.caudofasciata Shen et Chen is a junior synonym), C.lepidolepis Bleeker, C.leucura Gilbert (first record from Japan);C.margaritifer Fowler (often misidentified as C.dimidiata;C.bicolor (Macleay) is a homonym), C.mirationis Tanaka (C.fraenatus Araga et Yoshino is both a synonym and a homonym), C.notata (Temminck et Schlegel) (C.villadolidi Jordan et Tanaka and C.miyakeensis Moyer et Ida are synonyms), C.ovatiformis Fowler, C.ternatensis (Bleeker), C.vanderbilti (Fowler), C.weberi Fowler et Bean (often misidentified as C.xanthochir), and C.xanthura (Bleeker).C.alleni is described from specimens from the Ryukyus, Izu Islands, Taiwan, and Ogasawara Islands.It is dark yellowbrown, abruptly whitish on caudal peduncle and fin, with a large blackish spot at pectoral base.Allied to other small bicolored Chromis with produced filamentous caudal lobes, it differs in having modally 13 dorsal soft rays, 17 pectoral rays, and 15 or 16 tubed lateral-line scales.

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Two new species of gobiid fishes are described from coastal waters off the west coast of Colombia.One of them, Bollmannia gomezi, is described on the basis of five specimens and represents the ninth species of the genus in the eastern Pacific.The other new species, Lythrypnus solanensis, is based upon the unique holotype, and constitutes the sixth species of eastern Pacific Lythrypnus. Habitat preferences and zoogeographic data of the new species are indicated.

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A remarkable postlarva of 13.9 mm in standard length collected by surface tows of a larva net from the tropical western Pacific is described in detail, with special reference to its elaborated head and pectoral fin features.On the basis of morphological close fit, this specimen is identified with the genus Ipnops, family Chlorophthalmidae.Its specific name was tentatively referred to I.agassizi.This epipelagic larva is compared with recently transformed specimens, and possible metamorphosing process is discussed in relation to their drastic habitat change.It is clear that the flattened, dorsally-directed plaques unique to Ipnops are derived from the typical laterally situated eyes in pelagic larvae.

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Two rare zoarcids, Derjuginia ochotensis and Gengea japonica, are reported from the Okhotsk and Japan Seas.They are separable by dorsal rays (98 110 vs.90-94, respectively) and the relative position of the dorsal fin origin (advanced with anal origin below dorsal rays 7 10 vs.more posterior with anal origin below dorsal rays 1 N 3, respectively). Gengea is considered a synonym of Derjuginia.

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The abdominal vertebrae of the deep-sea perciform fish, Scombrolabrax heterolepis develop into a strange structure in the adult.Vertebrae 5th through 12th have expanded parapophyses that are bulged dorsolaterally to form a nearly hemispherical pocket on each side, opening ventrally.Delicate bubble-like evaginations of the gas bladder fit into the bullae.Because of the posession of unique features, percoid and scombroid characters, we propose to place the monotypic species in the family Scombrolabracidae and suborder Scombrolabracoidei in the order Perciformes.

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A new species of the family Triglidae, Lepidotrigla longifaciata, is described from Japanese waters.This species has been misidentified as Lepidotrigla spiloptera Günther.This species is characterized by the rostral projection with a round outer margin, 3 or 4 well-developed suprapostero-orbital spines, of which the outermost one is prominent, and stout supraorbital and postorbital spines.

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The larval and juvenile stages of the grey triggerfish, Balistes capriscus, are described and illustrated.In southern Brazilian waters larvae and juveniles were collected only during the summer season, especially in January cruises.They occurred not only at nearshore stations, but also at offshore stations near the margin of the continental shelf.

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Channa argus breathes air in the following manner: The opercula begin to abduct before the fish breaks the surface.The buccal cavity distends to transport gas from the air-breathing organ into the cavity.Expiration seems to be effected by a hydrostatic head and the contraction of the buccal and pharyngeal cavities, and is done directly into the air.Then the buccal cavity again distends to inspire air. The following abduction of the opercula transports the gas into the air-breathing organ while the branchiostegal membrane prevents the backflow of water.When the fish is breathing bimodally in water, nearly complete renewal of gas occurs at each air breath as evidenced by close agreement between composition of the gas in the air-breathing organ just after inspiration and that of the atmospheric air.When the fish is deprived from water, it violently struggles and repeats air breathing at a markedly higher rate.Ventilation of the air-breathing organ becomes less efficient in this condition, which is illustrated by lower Po₂ and higher Pco₂ of the gas throughout a breath hold.Our conclusion is that the gas in the organ is replaced by water entering the organ during expiration and then the water is replaced by inspired air when the fish breathes air during bimodal breathing.

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Complete hypophysectomy in male catfish Clarias batrachus elicits a sudden hyperglycemia, after two days of the operation.Along with a parallel rise in the alkaline phosphatase activity of the whole blood and the liver, a simultaneous fall was observed in the blood calcium, serum protein and liver glycogen and cholesterol contents.The sham operated fish did not show such alterations of significance.All the parameters rise quickly following injections of pituitary extract obtained from the male of C.bactrachus.

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The internal and endocrine organs of 8 specimens of the porcupine fish, Diodon holacanthus, were studied histologically.They were stranded on the beach of the Japan Sea in Niigata.Although they seemed to be in somewhat starved condition, no drastic emaciation was observed in the digestive tract, exocrine pancreas, kidney, and spleen, except for a large amount of fat deposition in the liver and regressive change in the thymus.The A cell considered to be a glucagon producing cell was predominant in the Brockmann body.The corpuscles of Stannius and the interrenal gland maintained healthy condition, while the thyroid gland showed a hypofunctioning state.The ovary was crowded with a number of previtellogenetic oocytes, whereas a large portion of the testis was occupied by the spermatogonia in addition to a small number of elaborate sperma-tozoa.A considerable amount of Gomori positive neurosecretory material was detected in the cells of the preoptic nucleus and pars nervosa.The putative gonadotrophs in the hypophysis contained only a small amount of glycoproteinaceous granules.Both the triggerfish Cantidermis rotundatus reported by Chiba et al. (1976) and the porcupine fish D.holacanthus, carried northward by the Tsushima warm current in winter and speculated upon as being immature fish on the way to an abortive migration, revealed a histologically similar condition.

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Thymic activity of the viviparous surfperch, Ditrema temmincki, was studied histologically throughout its life-span in relation to sexual maturity and gestation period.The materials used were caught on the coast of Aikawa Town, Sado Island in the Japan Sea, between June, 1978 and February, 1980.One hundred and sixty-six individuals were examined, including 123 adults, 16 juveniles and immatures and 27 fetuses.Males attain sexual maturity in August and begin mating.Mature eggs appear in November, and embryos, 1.5mm in total length, are seen in the following January.Since parturition occurs in June, the gestation period is suspected to be 6 months.The peak enlargement of the thymus in both sexes of adult individuals occurs in June with another lower peak appearing in October.There is a distinct difference in the thymic activity between the adult male and female in the early gestation period.From January to February, the thymic volume of females is remarkably larger than that of males.During this time, the thymus of the fetus is difficult to see due to its undifferentiated condition.The differentiation of fetal thymus begins in March when the fetus reaches 10mm in length.The mitotic figures of the large-and mediumsized lymphocytes are seen in this period.Toward April, small lymphocytes appear.The thymus of female fish is retained in an atrophic condition.However, a tremendous increase in its volume occurs in May and June, with a simultaneous increase in the thymic volume of the developing fetus.After parturition in June, the thymic volume of larval fish decreases month by month.In view of the relationship between the thymic volume of mother fish and fetus, the gestation period may be classified into three different periods: early (January to February), middle (March to April) and late (May to June).

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Quantitative fluoride analysis by electron microprobe was performed on the teeth and bone of marine teleosts of the order Tetraodontiformes (26 species).This order contains two suborders, namely, the Balistoidei which is a relatively primitive group and the Tetraodontoidei which is more advanced.Fluoride concentration in the enameloid of all the fishes examined from the Balistoidei was higher than 2.31 %, whereas that in the enameloid of all the tetraodontoids except for the Molidae was lower than 0.22 %.The enameloid of fishes of the Acanthuridae of the order Perciformes, from which the Tetraodontiformes may have derived, contained fluoride higher than 3.85 %.The dentin and bone of all the fishes examined contained flouride lower than 0.82 and 0.57 %.These results seem to indicate that the fluoride concentration in the enameloid is closely related to the phylogeny of fishes and that fishes of the Balistoidei have a peculiar ability to concentrate the fluoride to the enameloid (probably in the ectodermal enameloid-forming cells) and those of the Tetraodontoidei have lost this ability in the course of evolution.

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Development and distribution of larval zaprorid fish, Zaprora silenus Jordan, from the Bering Sea and around the Aleutian Islands are described.A total of 31 specimens of larvae, ranging in body length from 12.0 to 36.2mm, were collected with a 1.3-m ring net at 12 stations from June to August, 1971-1979.
Zaprora silenus is characterized by the dense pigmentation of black and brown stellate melano-phores which are found on the sides of the body through the larval period.The anus is located a little behind the middle of the body.Larvae were classified in three developmental stages: larval, prejuvenile, and juvenile stages.These included nine specimens excluding the minimum larva which was immeasurable, ranging in body length from 12.0 to 17.3mm, 10 specimens from 17.5 to 24.0mm, and 11 specimens from 26.9 to 36.2mm, respectively.In the larval stage of 17.3mm in length the body is surrounded by the fin fold, and the notochord is slightly flexed and 16 rays appear in the caudal area.Melanophores are present in the fin fold of the anal fin area.In the early prejuvenile stage the caudal elements are well developed.In the late stage the notochord is fully flexed and the caudal fin is formed.Although the full number of rays for each fin is present, the dorsal and anal fins still connect with the caudal fin.Several pigment bands appear on the dorsal and anal fins.In the juvenile stage each fin is completed and body proportions become constant.Seven to eight bands of pigment appear on the dorsal and three bands on the anal fin.
Two larvae were taken in the Pacific side of the Aleutian Islands, south of the Amchitka and Atka Islands.In the Bering Sea two specimens were collected north of the Tanaga and Adak Islands, and 25 specimens were captured above the 30m layer in the slope region at depths of 150 to 3000m from Unalaska Island to the Pribilof Islands.Two larvae were also collected in the basin area (latitude 58°N).The distributional pattern suggests that Zaprora silenus is planktonic during the larval and juvenile stages in the upper layer within the Alaskan Stream and the Bering Slope Current.

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Opisthocentrus tenuis Bean and Bean, 1897, is known from Hokkaido, Mutsu Bay, Aomori Pref., Iwate Pref.and Sado Island in Niigata Pref.This species dwells in small schools among Zostera in Mutsu Bay.It feeds mainly on benthic gammarids and caprellids, and usually swims slowly above the bottom in an L-shaped posture by fanning its large pectoral fins.
In Mutsu Bay, the spawning period seems to extend from early December to late January.The water temperature during this period falls to 5-10°C. From experiences with spawning experiments in the aquarium and observations on natural egg masses, the egg mass is always guarded by the spawned female.For studies in a small aquarium, a vinyl pipe was used as the spawning nest.In the natural site at Moura, Mutsu Bay, 5 to 6 m deep, each egg mass was found with the female parent coiled about it in a nest on the stony bottom.A female spawns only one time in one spawning season.
Eggs are attached to each other by their adhesive points, though they have no adhesive processes, and form a single spherical egg mass about 3 cm in diameter.The egg is translucent.The yolk is colorless, containing a large light yellow oil globule and many small ones with white cloudy materials surrounding the large oil globule.The egg membrane is about 2_3 mm in diameter.
Eggs spawned in the aquarium developed in water temperature varing from 4.6 to 8.0°C and larvae hatched about 58 to 64 days after the spawning.Newly hatched prolarvae, provided with large remnants of yolk, are slender and 11.0 to 11.8 mm in total length.The newly hatched prolarvae reach the postlarval stage about 20 days after hatching.Hatched larvae were reared in a small vessel for about two months.They were fed nauplii of brine shrimp Artemia sp., but the largest one reached only 19.0mm.
In May, 1979, at Moura, young fish, some more than 3 cm TL., were observed swimming close to the bottom in schools.From examinations of over four hundred specimens collected from Mutsu Bay, one year old fish seemed to grow to 6 to 10 cm TL., two year olds to 11 to 15 cm and three year olds to 16 to 19cm.Most fish attain sexual maturity in two years.The life span is two years in most fish.

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The examination of a species of Japanese gobiid fishes with five branchiostegals and completely separated pelvic fins revealed that it agrees well with the holotype of Riukiuia poecila Fowler, 1946, known only from the holotype.The fact that no specimen has been identified as R.poecila since 1946 is considered to be due to the original description, where R.poecila is described as having five dorsal spines, whereas the holotype actually has six.
Smith (1958) synonymized the genera Leioeleotris Fowler, 1934 (type species: L. zonatus) and Riukiuia Fowler, 1946 (type species: R.poecila) with Hetereleotris Bleeker, 1874 (type species: Gobius diadematus).As a result of our examination of the type species of the genera Hetereleotris, Leioeleotris, Lioteres Smith, 1958 (type species: L.caminatus), Chriolepidops Smith, 1958 (type species: C.nebulopunctatus), Satulinus Smith, 1958 (type species: S.zanzibarensis), and Dactyleleotris Smith, 1958 (type species: D.tentaculatus), and the subgenus Pseudolioteres (type species: Lioteres (P.) simulans which is synonymous with H.diadematus), we conclude that all of these should be included in the genus Hetereleotris, because they all share such common characteristics as protruding anterior and posterior nostrils, the first gill arch with most of the lower limb covered by membrane, broad isthmus and gill membrane attached to the base of pectoral fin, six dorsal spines, segmented caudal fin rays 9+8=17, completely separated pelvic fins without a frenum or a uniting membrane between them, five branchiostegals, vertebrae 10+17=27, first and second pterygiophores of first dorsal fin inserted between neural spines of third and fourth vertebrae and the last between those of sixth and seventh vertebrae, first and second pterygiophores of second dorsal fin spanning neural spine of ninth vertebra, an epural, and four transverse pit organ lines below eye and a longitudinal pit organ line touching the lower tips of the first three transverse pit organ lines and running to the fourth transverse pit organ line.
The relationship between the genus Hetereleotris and the genera Chriolepis, Eleotrica, and Gymneleotris of the seven-spined gobies of the Americas, which are said to be related to the genus Hetereleotris by Smith (1958), is not considered to be close, because, in addition to other differences, the genus Hetereleotris has a membrane covering the first gill slit, which is not found in these genera of the seven-spined gobies.The osteological comparison of H.poecila and H.zonatus with the genera Aruma, Pycnomma, and Gymneleotris of the sevenspined gobies revealed that, although the pelvic girdle of the genus Gymneleotris resembles the genus Hetereleotris, this, characteristic is not consistent in the other closely related genera Aruma and Pycnomma.This characteristic, therefore, does not seem to have any value in considering their relationship.
Pelvic fins without a frenum and with a vestigial condition of the uniting membrane are found in the various phylogenetic groups of gobiid fishes with five branchiostegals, but in these groups pelvic fins without a uniting membrane have been found only in the genus Hetereleotris.
The genus Hetereleotris is thus considered to be unique among the gobiid fishes with five branchiostegals, in having no closely related genera.

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Shapes of the swim bladders were studied for clarifying differences in three species of the genus Tribolodon, T.hakonensis (Günther), T.taczanowskii (Steindachner) and T.ezoe Okada et Ikeda, taken from several localities in Hokkaido. The feature of the tip of the posterior chamber of the swim bladder, with two types, is useful to distinguish between T.ezoe (round or grainy tip) on the one hand and T. hakonensis and T.taczanowskii (tapering or sharp tip) on the other hand. The length of the posterior chamber of the swim bladder was also different among the three species, i.e., it is longest in T.hakonensis, shortest in T.ezoe, and intermediate in T.taczanowskii.

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