While carrying out a preliminary survey of impounding fish population in May, 1959, the staff of the Tainan Fish Culture Station of the Taiwan Fisheries Research Institute found that the Chinese carps of the species Ctenopharyngodon idellus (C. & V.) and Hypophthalmichthys molitrix (C. & V.) had reproduced in the Ah Kung Tian Reservoir in the southwestern part of the Island.
This reservoir has an area of 360 hectares during the rainy summer season when water is high. The catchment areas of rain water run-off totaling 3, 320 hectares are among the hills at an elevation of from 100 to 300 meters (the base of the dam of this reservoir has an elevation of 26 meters above the level of the sea). The annual fluctuation of the water level is rather large, and has been about 7.5 meters in the past. The water of this impoundment has a surface temperature of from 12° to 34°C in annual range and is slightly turbid around the year. The dam of this reservoir was completed in 1952, when about 40 C. idellus and 900 H. molitrix fingerlings entered this body of confined water from a fish pond located near the site of the dam.
Both C. idellus and H. molitrix are the predominant species of fish in this impoundment. Based on the estimation made by a preliminary survey (TANG, 1959), the young-of-the-year C. idellus (in age-group 0) with total length ranging from 7.2 to 14.0cm numbered approximately 170, 000 and the H. molitrix measuring from 25.4 to 31.6cm in total length numbered approximately 20, 000 at the time of survey as mentioned.
Fisheries biologists are generally aware that the Chinese carps, except the species Cyprinus carpio, had not been reported to spawn elsewhere than in some rivers in the China Mainland. This, however, is no longer true, since it has been recently reported that three species, C. idellus, H. molitrix and Aristichthys nobilis, bred and became naturalized in the system of the River Tone in Japan (NAKAMURA, 1949; KURONUMA, 1954; INABA and NOMURA, 1956; INABA, NOMURA and NAKAMURA, 1957). The spawning of these fishes in confined waters, such as ponds, reservoirs or other types of impoundments, however, has never been reported, though they are the most important species of cultivated fish in China and her neighbouring countries for several centuries. Our present knowledge of the breeding requirements of the Chinese carps is far from complete, and the factor or combination of factors that actually governs the development of their sexual products or spawning in rivers or in confined waters has not yet been determined with certainty; it has been recently reported that the secretion of a hormone-like repressive factor has prevented reproduction in Cyprinus carpio, Carassius auratus, Megastomatobus cyrinella and Micropterus salmoides populations in the fresh waters of the United States (SWINGLE, 1954, 1956a and 1956b). In order to add our knowledge to this line and in the attempt to supply these fry locally, the Tainan Fish Culture Station is now conducting an intensive study program for investigating the breeding habits of these fishes and the hydrological conditions of this impoundment.

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In October, 1959, a serious case of intoxication caused by eating the flesh of a puffer of the genus Lagocephalus taken off Vietnam occurred in Kokura City, Fukuoka Prefecture, Kyushu, Japan. The present writer has been asked by Dr. Iwao TANI (Laboratory of Criminal Sciences, Fukuoka Prefectural Police Department) to identify the fish, and several frozen specimens and skeletons of the fish from the same water have been received for study through the courtesy of Dr. TANI, Mr. Takeo KAWAKAMI (Research Laboratory, Taiyo Gyogyo Co., Shimonoseki) and Dr. Toshiharu KAWABATA (Dept. of Food Control, National Institute of Health, Tokyo). The last-named biochemist and Mr. Koichi KAN-NA (Tokai Regional Fisheries Research Laboratory) have kindly revealed the presence of an unusually strong toxicity in the viscera, flesh and skin of the fish specimens dissected by the present writer. This fish resembles a Japanese form of Lagocephalus called “saba-fugu”, which is well known as non-toxic in Japan, and some fishermen shipped the former fish caught during the 2nd and 3rd of September, 1959, to Kyushu believing that it was, like the Japanese “saba-fugu”, not poisonous to eat. Some 340kg of the flesh (with vertebral columns and caudal fins) were sold by auction on the 16th of October, 1959, in Kokura City, and four persons died on the next day by eating the flesh in spite of the fishermen's effort to buy back the flesh from the purchasers; some of them working at a big restaurant ate tentatively a small quantity of the flesh in the evening of the 16th of October as they usually did, and in the next morning informed the retailer who sold the flesh of the puffer to the restaurant that it might be poisonous.
In the previous papers (ABE, 1942-1954), the present writer, with some doubt, disposed of Tetrodon spadiceus RICHARDSON as a synonym of Lagocephalus lunaris (BLOCH & SCHNEIDER). Examination of the frozen and skeletonized specimens of the poisonous puffer from off Vietnam mentioned above has led him to believe that it differs, morphologically as well, from the non-toxic congener from the Japanese waters which has hitherto been recorded either as Lagocephalus lunaris or as L. spadiceus.Although he is still doubtful of the identity of the latter fish with spadiceus described by RICHARDSON, it is thought advisable to give a new Japanese name for the poisonous puffer from Vietnam mentioned above and to discriminate between it and Lagocephalus lunais spadiceus from the Japanese waters. The poisonous puffer from Vietnam is believed to be Lagocephalus lunaris lunaris (BLOCH & SCHNEIDER). In the following pages the writer wishes to give a new Japanese name for it along with additional records of Lagocephalus lunaris lunaris and L. lunaris spadiceus, and finally present a key to these puffers. He takes pleasure in expressing here his thanks to the scientists who have co-operated with him.

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1. By means of hybridization experiments the presence of genetic affinity be tween Rhodeus sericeus amarus amarus from Western Europe and Rhodeus ocellatus from Japan could be established.
2. Both kinds of hybrids obtained from this combination were intermediate between the parental species and showed a male phenotype.
3. In the spawning season, both kinds of hybrids displayed full breeding colors and spawning behavior, but spermatogenesis was impaired.

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A trial study on the gas exchange was performed in carp.Curves showing the relationship between partial pressure and CO_2- or O_2- volume % contained in blood were obtained. In the carp respirating water from Marriot's flash the PCO2 PO2 were determined both in Aorta and in Vena. O₂ consumption was measured. Cardiac output was calculated.
Results obtained under the experiment arrangement are as follows.
1. PaCO₂ was about 13mmHg in 4 cases.
2. PvCO₂ was 16 to 39mmHg (average 30mmHg) in 4 cases.
3. PaO₂ was found to be 10 and 12mmHg in 2 cases. The small value must have resulted from the experiment arrangement.
4. PvO₂ was found 2mmHg. This suggests that the tissue of carp survives at a low Po₂.
5. The difference in CO₂-vol % between Aorta and Vena changes according to that in O₂.
6. Both PaCO₂ and PvCO₂ are very small in comparison with those in man . On contrary, ΔPCO₂ in carp exceeds that in man.
7. At periphery the arterial blood liberates 80% of O₂ contained.
8. It seems probable in carp exposed to the atmosphere that gas exchange proceeds to some extent.
9. Cardiac out put in carp was calculated to be about 13cc/min. kg.

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The normal developmental stages of the goldfish (Carassius auratus) has been described, a summary of which is as following table.
Stage 1.-Unfertilized egg. (Fig. 1)
Stage 2.-Fertilized egg. (30 minutes; Fig. 2)
Stage 3.-2-cell stage. (1 hour; Fig. 3)
Stage 4.-4-cell stage. (1 1/2 hours ; Fig. 4)
Stage 5.-8-cell stage. (2 hours ; Fig. 5)
Stage 6.-16-cell stage. (2 1/2 hours ; Fig. 6)
Stage 7.-32-cell stage. (3 hours ; Fig. 7)
Stage 8.-Morula stage. (3 1/2 hours ; Fig. 8)
Stage 9.-High blastula. (4 hours ; Fig. 9)
Stage 10.-Flat blastula. (5 1/2 hours ; Fig. 10)
Stage 11.-Expanding blastula. (7 hours ; Fig. 11).
Stage 12.-Early gasturula. (9 1/2 hours ; Fig, 12)
Stage 13.-Middle gasturula. (11 hours ; Fig. 13)
Stage 14.-Late gasturula. (13 hours ; Fig. 14)
Stage 15.-Early embryonic shield. (15 hours ; Fig. 15)
Stage 16.-Late embryonic shield. (18 hours ; Fig. 16)
Stage 17.-Optocole develops. (21 hours ; Fig. 17)
Stage 18.-Optic vesicle develops. (26 hours ; Fig. 18)
Stage 19.-Optic cup and lens develops. (30 hours ; Fig. 19)
Stage 20.-Tail bud stage. (33 hours ; Fig. 20)
Stage 21.-Retinal pigmentation begins. (36 hours ; Fig. 21)
Stage 22.-Melanophores first appear on embryo. (50 hours ; Fig. 22)
Stage 23.-Heart pulsates, and circulation begins. (60 hours ; Fig. 23)
Stage 24.-Pectoral fin bud appears. (80 hours ; Fig. 24)
Stage 25.-Hatching. (100 hours ; Fig. 25)
Stage 26.-Air bladder develops. (2 days after hatching ; Fig. 26)
Stage 27.-Tail fin rays develop.(7 days ; Fig. 27)
Stage 28.-Dorsal and anal fin rays develop.(3 weeks ; Fig. 28)

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The external and histological features of pituitary gland of sea-lamprey, Lampetra (=Entosphenus) japonica (MARTENS), are described. The specimens were collected from the Ohkozu river, a branch watercourse of the River Shinano in Niigata Prefecture, at the time of ascending the river with the approach of its breeding season.
1. The pituitary components of L. japonica consist of four parts, which are similar to those of higher vertebrates ; they are subdivided into three glandular (or adenohypophysial) parts and a neural one. Thus, the following nomenclature would be applicable to these constitutional components: (1) pro-adenohypophysis, (2) mesoadenohypophysis, (3) meta-adenohypophysis and (4) neurohypophysis.
In general three parts of adenohypophysis are separated respectively with the septa of connective tissue, there is a streak capillary between meta-adenohypophysis and neurohypophysis.
2. Pro-adenohypophysis is mainly composed of the masses of cyanophilic and acidophilic cells which are disposed in vertical rows. Though this part has been named anterior lobe or medullary core of pars distalis, it seems to be homologous to pars principalis of pars anterior in higher vertebrates.
3. Meso-adenohypophysis is composed of predominant acidophilic cells which are also disposed in vertical rows. This part has been named Ubergangsteil or cortical zone of pars distalis, however a part of this is presumed to be homologous to pars tuberalis of pars anterior in higher vertebrates.
4. Meta-adenohypophysis is mainly constructed from high columnar acidophiles which are disposed in a band or a cord, and is unique part which keeps touch with neurohypophysis. Though the previous investigators called this part intermediate lobe or pars infundiburalis, this seems to be homologous to pars intermedia of higher animals.
5. Neurohypophysis is merely an expanded part of ventral wall or floor of recessus infundibuli, and consists of two parts, which are the cellular part originated from the ependyma of brain at the dorsal region and the neuroglial part at the ventral region.

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The present paper contains an introductory notes on Lake Suwa, Nagano Pre fecture, Japan, with a brief history of the study on the fishes of this lake, from 1909 to the most recent (1956), and a complete list of the fishes of Lake Suwa (32 species and subspecies, including 5 new additions), found in the lake itself, in addition to a note on the African Tilapia sp. and Entosphenus reissneri in the Cyclostomata.
The mark * indicates the occurrence of the introduced forms (9 in number) found in the lake itself.

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The part nine of this series contains descriptions of life colors of the species Nos. 132-143, with some interesting notes on Tosana nitvae, Pomacentrus fumeus, Halichoeres tenuispinnis, etc. from Suruga and Sagami Bays.

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In this paper is given description of Idiacanthus panamensis (female of total length 420 mm.) from a depth of 1000 m., off Kesennuma (Miyagi Pref.) by our research boat, No.1 Asahi-maru (56 ton), and chartered boat, No.10 Shinkai-maru (51.6 ton) during survey of deep-water fishing grounds (500-1000 metre depth) in bottom trawl without otter boards in Tohoku and adjacent region during July-October, 1951, and the result of measurement of the four specimens (total length 260, 134, 112 and about 84mm.) taken from the stomachs of Theragra chalcogramma (PALLAS) caught off Hachinohe in August, 1958. The specimens well agree with to the key to the species of this genus by REGAN and TREWAVAS (1930), but all body propotion has not characters of I. panamensis, but in some points have characters of I. fasiola.
According to REGAN and TREWAVAS (1930) photophores from pelvics to origin of anal number 15-18 in I. fasiola, and 16-22 in I. panamensis, but my specimens have 23-24.
Further I added the distribution records of this species in Japanese water; hitherto it is known from Kumano-nada and off Kochi.

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At least three species of lutjanid fishes of the genus Paracaesio are taken commercially off the Pacific coast of southern Japan*. They are all prized as food, and shipped to the Central Wholesale Market of Tokyo in considerable quantity (usually one to five metric tons per day). It is remarkable to note that one of them, though well recogniazed at least by experienced middlemen at this market, seems not to have been described. In view of the progress of the survey of the marketable fishes of the islands lying south of Tokyo, it is thought timely to describe this new species here. The present writer takes pleasure in expressing here his sincere thanks to Prof. S. SHINOHARA (Ryukyu University, Okinawa Island) and Mr. T. KUSAKARI (Hachije Branch, Tokyo Prefectural Fisheries Experiment Station, Hachijo Island) for their co-operation with him.

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