相模湾からハナダイの2新種を漁獲した.1種はチゴハナダイPlectranthias altipinnatusで, 1977年伊豆海中公園富戸沖の水深40mの岩礁地帯から1尾採集された.本種はケニア産のPlectranthias morginsi (Smith) に似ているが, 背鰭軟条数の多いこと, 尾鰭分枝軟条数の少ないこと, 体高が低いこと, 眼が小さいこと, 背鰭, 臀鰭軟条部基底に鱗があることなどで区別される.他の1種はアサヒハナゴイAnthias (Mirolabrichthys) flayoguttatusで1979年伊豆大島近海の水深50mの岩礁地帯から4尾採集された.本種はニューカレドニア産のAnthias lori Fourmanoiret Labouteと極めてよく似ているが, 臀鰭第1棘が長いこと, 側線鱗数が少ないこと, また体色などの相違がある.

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アベハゼMugilogobius abeiの産卵行動, 産卵期, 卵および仔魚の発育を観察した.産卵期は4月から8月にわたり, 5, 6月が盛期であった.産卵は1個体の雌によって, 複数回行われることが判った.卵は楕円形で, 平均長径0.98mm, 短径0.45mmであった.卵発生の観察開始後, 卵は97時間 (水温24.0°～24.6℃) で艀化した.飼育した仔魚は, 艀化後44日頃 (水温225°～29.1℃) にすべて底棲生活に移行した.野外における仔魚は, 浮遊生活を終えた後, 徐々に本来の生息地に帰ってくることが推察された.

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食用ゴイの品種的特性を明らかにするために, 日本産およびヨーロッパ産5品種の計数的および体形的差異を調査した。各品種の標本は, 3種類の異なった環境下, すなわち (1) 施肥養殖, (2) 流水式給餌養殖, および (3) 止水式給餌養殖で飼育されたものが用いられた。計数的諸形質では, いずれの環境下においても, カガミゴイ≈ドイツ産ウロコゴイ>ヤマトゴイ>アサギゴイミ野生ゴイの関係が, また体形的諸形質では, カガミゴイ>ドイツ産ウロコゴイ>アサギゴイ>ヤマトゴイ>野生ゴイの関係がみられた.すなわち, ヨーロッパ産養殖品種は日本産養殖品種よりも, ほとんどの計数的形質や体形的形質の数価が高く, 野生種はそれが最も低かった.

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佐渡島沖から得られたバショウカジキの成魚と未成魚を用い, 視床下部―下垂体系および甲状腺を光顕レベルで検索した.下垂体には7種類の腺細胞が検出されたが, 未成魚の甲状腺刺激細胞は塩基性色素で強染され, 甲状腺は機能亢進状態を呈していた.成魚の生殖腺刺激細胞には脱顆粒や空胞化した肥大細胞が認められ, 経産個体と推定された.神経葉と視束前核およびその軸路には, AF陽性の神経分泌物が相当量検出された.隆起部外側核は側部と腹内側部の二部からなり, 成魚の腹内側部の細胞には酸好性顆粒を充満した小嚢構造がみられたことが特異的であった.

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Six species of the genus Bathygobius collected in Japan were compared with each other and with the type specimens of nominal species considered as synonyms of three species of the genus Bathygobius: B.petrophilus, B.scapulopunctatus, and B.fuscus listed by Koumans (1953).
The genus Bathygobius has the following combination of characters: a protuberance below the anterior nostril bordered by a groove containing pit organ line 6 on the upper side and by a groove containing pit organ line 7 on the posterior side, a median longitudinal groove containing pit organ line 10, which runs from the anterior margin of the cheek and divides into two posteriorly, the trapeziform mental flap bordered by a groove containing pit organ line 13 on the lateral side and by a groove containing pit organ line 14 on the posterior side, and free branched rays on the upper part of the pectoral fin.
Six species of the genus Bathygobius were found in Japan, i.e., B. fuscus, B.padangensis, B.cocosensis, B.petrophilus, B.cyclopterus, and B.cotticeps.
The differences between B.fuscus and B.padangensis are the least among the six species.Clearcut differences between them are only in the number of free branched rays on the pectoral fin and in coloration, although there are some specific differences in the number of pectoral fin rays and the angle between the lower and posterior axes of the first pterygiophore of the first dorsal fin. The number of differences between B.padangensis and B. cocosensis and between B.fuscus and B.cocosensis are only slightly greater. Although more differences are found between B.cyclopterus and B. cotticeps than those among the three species mentioned above, both of them have many common characteristics, some of which are specialized and are only found in these two species.
Based on the number of common and distinctive characteristics, the six species are divided into three types: B.fuscus, B.padangensis, and B.cocosensis; B.petrophilus; B.cyclopterus and B.cotticeps.
B.fuscus, B.padangensis, B.cocosensis, B.cyclopterus, and B.cotticeps are found in the tidal zone of rocky beaches, while B.petrophilus is collected near shore on substrates of sand or mixed mud and sand. B.fuscus, B.padangensis, and B.cocosensis are collected north of 35°N, but specimens of B.padangensis and B.cocosensis collected in the northern area of their range are extremely small in number compared with those of B.fuscus.B.petrophilus is collected between 33° and 35°N in Japan, but as the type specimens of Gobius petrophilus and Gobius villosus were collected in Indonesia, it is conjectured that B.petrophilus inhabits southern Japan south of 33°N.
The examination of the type specimens revealed that Gobius poecilichthys should be synonymized with B.fuscus which is different from Mapo fuscus sensu Jordan, Tanaka and Snyder (1913).M. fuscus sensu Jordan, Tanaka and Snyder is presumed to be synonymous with B.padangensis from the description of M.fuscus sensu Snyder (1912a) from Tanegashima, in which the difference between M.fuscus and Mapo poecilichthys was recorded, and from the specimens of M. fuscus sensu Snyder (1912b) from Naha.
Bathygobius sp.reported by Arai and Ida (1975), Zama and Fujita (1977), Hayashi and Itoh (1978) was identified as B.cocosensis on the basis of comparison with three specimens of that species (RMNH 4533) collected and identified by Bleeker.

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The leptocephali of the snake eel, Muraenichthys gymnotus Bleeker, were collected from the inshore waters of Tosa Bay, Kochi Pref., Japan, from October through December in 1976 and 1977.The premetamorphic larvae are small, ultimately reaching about 70 mm in total length just before the onset of metamorphosis.The number of larval teeth is expressed by 0-1 (grasping tooth) +0-V (anterior teeth) +0-8 (posterior teeth) in the upper jaw, and 0-1+I-VI+0-4 in the lower.
The pectoral fin is feeble and short, about 5 times in head length.The origin of the dorsal fin is situated slightly in advance of the anus.The total myomeres are 131 to 140, preanal myomeres 66 to 70, and postanal myomeres 64 to 71.The anterior margin of the gall-bladder is at level of myomeres 18 to 23, the 1st vertical blood vessel at myomeres 16 to 20, the last vertical blood vessel at myomeres 58 to 65.The alimentary canal is long and narrow, looped slightly in 6 to 9 places.The pigmentation of the body is conspicuous and characteristic.
From the results of our rearing experiment, it can be concluded that the metamorphosis of the larvae is accomplished rapidly in about one week.The larval teeth on both jaws are lost entirely on the 2nd day after the onset of metamorphosis, and the conical teeth begin to appear on the 5th day.During the metamorphosing stage the position of the anus slowly moves forward, then the dorsal fin originates above or slightly behind the anus on the 5th day.Small melanophores are scattered on the snout, lower lip and dorso-lateral surface of the body on the 4th day.The total length reaches its minimum size, 51.2 mm in average, on the 5th day.
The juvenile stage lasts for about 20 days in the rearing experiment.The body is well elongate, its depth is lower than 30 times in total length.The pectoral fin is scarcely visible or entirely absent.In the last juvenile stage the dorsal fin originates behind the anus at a distance about equal to the length of the snout, and the bodys are colored with light brown.
The premetamorphic larvae cease to be planktonic and burrow themselves into the sand bottom just before metamorphosis.The snake eel is a typical head burrower throughout metamorphosing and juvenile stages.

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Fish fauna at the inshore rocky reefs in Shirahama was investigated by underwater observations using SCUBA almost bimonthly during the period from 1973 to 1977.About 300 species were recorded in total.The number of species increased in summer and autumn, but decreased in winter.According to seasonal occurrence, the fishes observed are grouped into four types: 1) year-round resident species (Y-type);2) species which reside all the year round in years of warm winter waters, but appear only as juveniles from July to January in years of cold winter waters (Ya-type);3) species of which only juveniles appear almost restricted to the period from July to January (A-type);and 4) species which appear both as adults and juveniles only in the warmer period from May to November (S-type).Most of the species belonging to the A- and Ya-type are smaller tropical fish, strongly dependent on coral or rocky reefs, whose juveniles are seemingly transported to this area by the warm Kuroshio Current from southern areas, and very rarely survive over winter in coral or rock crevices.Most of S-type species are larger fish which probably migrate offshore to deep reefs during the colder period.Accordingly, there seems to be a difference in the range of elasticity in the modes of life of these various types.
Two main strategies against the low temperature in winter in southern or tropical species are suggested: “winter sleep” in substrate-dependent smaller species and “offshore migration” in mobile, larger species.

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Color anomalies occur frequently in hatchery-reared young of the flouder Paralichthys olivaceus.The anomalies usually accompany aberrations in other external characters as described for natural populations of flatfishes.
In normally colored individuals, the squamation on the ocular side started along the posteror half of the lateral line at 20.2 mm in total length and was complete at 54.0 mm.Squamation in individuals with anomalous coloration started on both ocular and blind sides at 22.1 mm in TL, and was completed at 51.8 mm.Though squamation started at the same part of the body in both normal and anomalous fish, development of squamation on both sides was more rapid in normal individuals than in anomalous ones.In normal fish greater than 50 mm in TL, scales were larger and had more spines and ridges than in anomalously colored individuals.

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台湾東海岸, 台東県成功鎮のタイドプールから得られたハダカハゼ属の1種Kelloggella camdinalis雌雄各1個体について記載した。本種は台湾初記録であり, 本報告は本種の分布域の最北記録である.

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駿河湾と和模湾からヤマヒメ2尾が採集された.ヤマヒメは採集例が少なく, 従来, 鹿児島から2尾が記録されているのみである.この採集記録によって, 本種が本州中部海域家で分布することが明らかとなった.また, ヤマヒメの新鮮時の体色も記載した.

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沖縄県石垣島川平湾とその周辺水域において, フイリピン周辺までの分布が報告されていたApogon compressus (ヒラテンジクダイ), Apogon sangiensis (サンギルイシモチ), と太平洋ギルバート諸島からだけ報告されていたApogon giliberti (ウスモモテンジクダイ, 新称) を採集した.これち3種のテンジクダイ科魚類は日本からの初記録である.
Apogon gilbertiの学名を採用するにあたり, 近似種のApogonfrgilis, Apogon leptacanthusなどと外部形態や測定値の比較を行い, A.fragilisはAgilberiのジュニアーシノニムであると認めた.

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カレイ目魚類3種, ヒラメ科のヒラメおよびウシノシタ科のクロウシノシタとゲンコの体細胞染色体を通常のair-drying法により観察した.染色体数はヒラメ2n=46, クロウシノシタ2n=38, ゲンコ2n=34である.ヒラメの核型は23対の端部着糸染色体から構成され, NF=46である.最も大きい端部着糸染色体対にこれまでヒラメ科魚類の核型では報告されていない二次くびれが観察された.クロウシノシタの核型は3対の中部着糸染色体, 1対の次端部着糸染色体および15対の端部着糸染色体からなり, NF=46である.ゲンコの核型は17対の端部着糸染色体から構成され, NF=34である.
これら3種の核型はいずれも腕数が少なく, カレイ目魚類の中では特異的である.

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日本産アイナメ科魚類4種, ホッケ, クジメ, エゾアイナメおよびウサギアイナメの体細胞染色体を通常のair-drying法により観察した.染色体数は4種とも2n=48である.各種の染色体構成を表に示した.
クジメの最も小さい次端部着糸染色体対には付随体が観察された.これら4種の核型は種類により明瞭に異なり, 有効な分類形質となり得ること, および他のカサゴ目魚類のそれらと比較してかなり複雑であることが判明した.

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