大阪湾において2012–2014年の8–10月に出現したウシノシタ科稚魚について形態および分布を調査した．調査ではイヌノシタ，

，ゲンコの3種が採集された．イヌノシタは背鰭，臀鰭鰭条数で他2種と識別され，鰭条数範囲が重なるとゲンコは左眼と口の位置関係，有眼側の黒色素胞の分布や眼径により識別が可能であった．最小サイズは，イヌノシタで標準体長（以下，SL）9.6 mm，7.2 mmSL，ゲンコ11.0 mmSLで，は他2種に比べ10 mmSL未満の割合が高く，着底サイズは3種の中で最も小さい10 mmSL未満と推定された．イヌノシタ稚魚は主に8, 9月に湾中央部の水深20–30 mに，稚魚は主に10月に湾北部の水深10–20 mに，ゲンコ稚魚は主に10月に湾全域の水深10–30 mに分布する傾向がみられ，種により分布が異なった．

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コウライの自然産出卵を用いて，各発生段階までの到達時間，ふ化までの所要時間およびふ化率に及ぼす水温の影響を調べた。13～24℃の範囲で発生が進行し，ふ化仔魚が得られた。各発生段階への到達時間は，水温の上昇とともに指数関数的に減少し，ふ化開始までの所要時間は30時間30分～102時間であった。水温とふ化所要時間の対数との関係は，20℃付近に変曲点が認められ，変化率が異なった。正常ふ化仔魚が得られた水温範囲は13～24℃，そのうち50%以上の正常ふ化率を示した範囲は13～20℃であった。最も正常ふ化率が高かった水温は15℃および17℃であった。これらの結果から，コウライの卵発生とふ化に最適な水温は15～17℃付近と考えられ，岡山県における本種の自然産卵盛期の水温と一致した。

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We investigated the morphology of cynoglossid larvae with elongated dorsal double rays collected in Osaka Bay. Larvae were divided into three types based on the distribution of melanophores on the lateral surface of the tail. Type A had melanophores along the midline of the tail. Type B had no melanophores along the midline, but had melanophores scattered near the center of the tail. Type C had no melanophores on the lateral surface of the tail. Type A, B, and C were collected in August–November, August–October and July–October, respectively. The range of the body length (BL) of each type were as follows, A: 4.0–12.4 mm; B: 3.4–7.8 mm; C: 2.1–9.6 mm. There were no individuals larger than 8 mm BL in type B. In type C, all but two individuals larger than 9.5 mm BL, were smaller than 5.2 mm BL. Types A and B had similar numbers of dorsal, anal and caudal fin rays (D ≤ 115; A ≤ 88; C 10) and myomeres (M 48–50) but could be distinguished by ratios of the body depth and preanal length to BL. In type A, notochord flexion had not begun at 7 mm BL but in type B, notochord flexion was complete at ca 7 mm BL. The numbers of fin rays and myomeres of type C larger than 9.5 mm BL (D 125–130, A 101–102, C 10, M 58–59) differed from type A and B; however, type C smaller than 5.2 mm BL had similar numbers of myomeres and proportion to type A and B. Our analysis of cynoglossid larvae and the characteristics of cynoglossid fishes occurring in Osaka Bay i.e., Arelia bilineata, Cynoglossus abbreviates, C. interruptus, C. joyneri, C. robustus and Paraplagusia japonica, suggest the following; type A: C. interruptus; type B: C. joyneri; type C (larger than 9.5 mm BL)：C. robustus. Type C smaller than 5.2 mm BL were likely to be C. joyneri or C. interruptus. Results of our study provide a first attempt at a description of C. interruptus larvae. Our results differ from some previous reports, which described the morphology of C. joyneri and C. robustus larvae and it is possible that individuals identified as C. joyneri larva in previous studies included C. interruptus or C. robustus larva. Discrepancies between the results of the present and previous studies suggest that further study will be required before the cynoglossid larvae can be positively identified.

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個別飼育したコウライ天然魚の産卵間隔，産卵数，産卵時刻等について調査した。4月下旬から6月上旬に4例すべてで14～22回の産卵が確認され，本種が多回産卵魚であることが明らかになった。産卵水温（13.7～19.9℃）や産卵頻度（44～81%）には個体差があり，産卵間隔に一定の傾向はみられなかったが，盛期には毎日産卵することが確認された。雌1尾あたりの産卵数は最大45～53千粒/日，期間中の総産卵数は334～521千粒であった。対照とした複数雌の群産卵区では，浮上卵率（0～100%）と卵径（0.96～1.10 mm）は産卵期の進行とともに低下し，水温と負の相関が認められたが，個別産卵区では浮上卵率において相関が認められず，個体と集団の示す卵質傾向は異なることが示唆された。産卵時刻は14～0時と推定され，16～22時の産卵数が全体の7割を占めた。

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岡山県東部海域において，ウシノシタ科3種の食性を把握するため，消化管内容物と筋肉部の炭素・窒素同位体比を調べた。3種とも，端脚類，クーマ類，エビ類およびカニ類を中心に多毛類，二枚貝類等を加えた多様なベントスを摂食し，全長の増加とともに大型のベントスを摂食していた。3魚種のδ¹³C 値は－17.3～－14.9‰と一般に報告されている微細藻類の値に近い値を示したことから，これらの種は底生微細藻類を炭素供給の起源にしていると考えられた。一方，3魚種のδ¹⁵N 値は17.8～20.3‰の範囲で，大阪湾のウシノシタ類のδ¹⁵N 値よりも明らかに高かった。したがって，本調査海域では一次生産段階からδ¹⁵N 値が高められていると考えられ，人為的な窒素負荷が影響していることが示唆された。

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The early life history of a tongue fish Cynoglossus joyneri GÜNTHER was studied in the western Wakasa Bay, the Japan Sea.
General morphology of the larvae and juveniles ranging from 5.75mm to 16.25mm BL, was described. The characteristic features of the fish in early larval stages were elongations of the first 2 dorsal fin rays and distributional patterns of melanophores on the body surface.
Judging from gonad index and occurrence of larvae, actual spawning may occur during relatively long period from July to September in the western Wakasa Bay.
Early poslarvae were caught mainly off Wakasa Bay, and late postlarvae were caught in the inner part of the Bay. Early juveniles were captured in the shallow water of the Bay, and this area may be their nursery ground.
Food items in the gut contents were as follows: small copeods Microsetella norvegica and copepod nauplii in early larvae, copepods Paracalanus sp and M. norvegica in metamorphosis, and copepods Paracalanus sp. in early juveniles.

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コウライ仔稚魚期の適正水温を明らかにするため，14，17，20℃および自然水温（16～24℃）でふ化仔魚から着底稚魚まで飼育し，成長，生残，変態，形態異常に及ぼす影響を検討した。仔稚魚の成長は14℃<17℃≒自然水温<20℃で，水温が高い順に速かった。生残率も14℃<自然水温≒17℃<20℃と，水温が高いほど高い傾向があり，14℃区では飼育が困難であった。全ての水温区で眼位など頭部周辺と体色に形態異常がみられた。正常個体率は17℃を最高に低温および高温側で低い傾向が確認され，自然水温で最低，次に20℃区で低かったことから，20℃以上では形態異常の出現率が高まる可能性が示唆された。本種仔魚の成長や変態を速め，稚魚の生残率と正常個体率を高める飼育適水温は17～20℃と推察された。

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Cynoglossus abbreviatus spawns from mid-March to mid-April in the Sea of Shimabara in Kyushu. During the spawning season ovarian maturation was successfully induced by injection of the pituitary homogenate of Hypophthalmichthys molitrix. The dose of the aceton-dried pituitary homogenate was 6.5 mg/kg body weight of C. abbreviatus. It took about 2 days for ovulation after injection at a water temperature of 14 to 16°C. Artificial fertilizations were accomplished on March 29, 1974 and again on April 7, 1984, using the females matured by hormone injection in the latter case only. The larvae were reared on the rotifers, Artemia nauplii, Tigriopus japonicus and copepods collected from the sea over a period of 113 days in 1974 and 58 days in 1984. The eggs were pelagic, spherical, 1.19-1.23 mm in diameter and had 30-50 oilglobules of 0.068-0.095 mm in diameter, and the perivitelline space was narrow. The incubation period was 90-98 hours at a water temperature of 14 to 16°C. The newly hatched larvae were 3.18-3.45 mm TL and had 61-64 myomeres. The larvae had many melanophores and xanthophores on the body, forming three bands on the caudal region, but were lacking chromatophores on the finfolds. The yolk was completely absorbed when the larvae attained a size of 4.7-5.6 mm TL 8 days after hatching. A single elongated dosal fin ray developed on the head in the 8-day old larvae. The ray was reduced in size as long as the other rays 1 or 2 days after metamorphosis. The rudiment of pectoral fins were found on the both sides of the body in the 2-day old larvae, but two of them disappeared after metamorphosis. A pelvic fin first appeared as a ventral bud just anterior to the gut in the larva of 8.39 mm TL. The full count of 4 rays was observed on the larva of 10.83 mm TL. Metamorphosis began 22 days after hatching when the larvae were 11.20 mm TL. The right eye began to shift the left side of the head at night and reached to the final place after 8.5 hours. It took about 36 hours to complete the metamorphosis, including the eye movement and fusion of the hole in the rostral beak. At the last stage of metamorphosis, the dosal, caudal, anal and ventral fins became confluent. The larvae reached the juvenile stage at a size of 13.5-14.0 mm TL, approximately 28 days after hatchling. The growth of larvae reared in 1974 is expressed by the following equations:
Y₁=3.448·1.0507^x (8≤X≤28)
Y₂=6.3322·1.0275^x (28≤X≤75)
where Y is the total length (mm) and X is the number of days after hatching. Growth rate changed after metamorphosis.

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The growth differentiation found among 19 Japanese soles obtained from southern part of Japan is quantitatively viewed with several biological aspects.
At the age of 3 years, the body reaches 100mm or even becomes longer in the fishes belonging to the subfamily Synapturinae, but in those of the other subfamilies of Soleidae (Soleinae and Achirinae) it is usually shorter. In the family Cynoglossidae, the members of the subfamily of Cynoglossinae attain on the whole more than 100mm in the body length, whereas the fishes of the Symphirinae never reach 100mm.
According to extremity body length calculated by the difference diagram, each of the tropical, subtropical and temperate forms is clearly divided into 3 groups. But the tropical form is always more or less longer than the others (Fig. 3). It also seems probable that in the same genus the species originated in the tropical ocean have a longer body than the endemic ones of Japan and China (i.e.: Zebrias zebra-Z. japonicus, Aseraggodes kaianus-A. kobensis, Symphurus strictus-S. orientalis).
There is a tendency in this group that the higher counts anal soft rays the fish has, the larger the body becomes.

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The early life history of a tongue fish Paraplagusia japonica (TEMMINCK et SCHLEGEL) was studied in the western Wakasa Bay and adjacent waters, the Japan Sea.
General morphology of the larvae and juveniles ranging from 5.95mm to 12.30mm BL was described. The characteristic features of this fish in early larval stages were elongations of the first 2 dorsal fin rays and distributional patterns of melanophores on the body surface.
Judging from gonad index and occurrence of larvae, acutal spawning may occur during the relatively short period from June to July in the western Wakasa Bay. Early postlarvae, late postlarvae and early juveniles were caught mainly in Maizuru Bay, Yura River estuary and nearshore regions around Wakasa Bay. These areas may be their spawning and nursery ground.
Food items of the gut contents were as follows: copepods nauplii, small copepods and copepod eggs in early larvae, copepods and copepod nauplii in metamorphosis, and, copeopds and amphipods in early juveniles.

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The author has enumerated four species of fishes with some notes. Among them Ranzania makua and Trulla itina are newly added to the list of the fishes of Suruga Bay, Japan. Hypoptychus dybowskii should be. erased from this' list.

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