Inland Sea Of Japan Research Articles

THE GEOMORPHOLOGICAL DEVELOPMENT OF THE NORTH-WESTERN OSAKA PLAIN

The Osaka Basin which is located in the east end of the Inland Sea of Japan, is filled with the Plio-Pleistocene deposits, so called the Osaka Group, of clay, sands and gravels. It graddually becomes of marine origin with alternation of marine and nonmarine stratum. The Plio-Pleistocene is exposed in the platforms and the hills in and around the Osaka Plain of which the height ranges from several tens meters to about 200 meters. On the sides of the surrounding mountains, we observe the disturbed Osaka Group, influenced by the uplifting movement of the mounatins. Generally speaking, it is complicatedly disturbed by f lexture, fold and overthrust, but it is safely concluded that the Plio-Pleistocene is dislocated to rise generally from the deltaic plain to the margins of the basin, and, so to say, that the Plio-Pleistocene deposits slightly decline to disappear into the bottom of the bay, or below the deltaic deposits. In another view, the the distribution of the deltaic deposits can be said to be restricted to the depressed area, provided by the basin building movement. The hills in the uplifted area present tectonic morphology. The late Pleistocene platforms of which the inclination be comes steeper with their being older (higher), cut the Osaka qroup which dips in the same direction. Both the surfaces or the prolonged surfaces of the platforms cross together and sink into the deltaic deposits in the depressed area. On the other hand, the Pleistocene below the deltaic deposits, it is suggested by boring, have sedimentary cycle of clay and gravels or coarse materials. It can be said hypothetically that the sedimentary cycle is possibly of eustatic origin. To say conclusively, the geomorphology of the hills is under the control of tectonic movements, but eustatic control is over the sedimentation below the delta. The several hundreds of boing data in which the locations of the main ones are shown in Fig. 1, show us that each layer is slightly declined toward the central part of the bay. And as are shown in Fig. 2, the deeper the layers are, the steeper the inclination. The clayey deposits decrease in the thickness toward the uplifted area of the hills of the Plio-Pleistocene. Such inclination is significanty accordant to that of gravels on the platforms. It is due to basin building movements (or tilting movement). The correlation of the data of boreholes makes us conceive that two epoch-making ground surfaces still remain to be buried below the deltaic deposits. The Fig. 3 shows the younger buried surface which is formed during the lowering of sea-level of the last glacial age in the consideration of the radiocarbon chronology of a piece of wood on the gravels. The surface is terraced, as is shown in Fig. 3. The terrace emerges from the deltaic deposits, forming the platform, with steep cliffs, which is dotted surface of Fig. 1. The older surface below the younger is shown in Fig. 5. It cuts flat the underlying layers as shown in Fig. 2, c. The older surface is considered to be correlated with the upper platform in the plain. The clayey or silty deposits containing shells between the two gravels (Fig. 2, o) is accumulated during the transgressive period. It is the basin-building movement of the Osaka plain that preserved the old landforms in the depressed place., byburying them in the materials from the uplifting area. The late-pleistocene geomorphological process of the north-western Osaka Plain can be schematically represented as shown in Fig. 6, (I). The surface of gravels is formed in the order of I, II, III. In case the quantity of the deposits in the depressed area, is negligibly scanty, or the relative rise of sea-level is so rapid that sedimentation can not keep up with it, the scheme of it will be (II) of Fig. 6. In rapanese Islands, such tilting movement in depositional plain seems to be commen process.

Fecundity and spawning of a puffer, fugu rubripes (T. et S.) in the central waters of the Inland Sea of Japan

トラフクの産卵については従来まったく知られていなかった.われわれは， 1960年および1961年の4-5月，瀬戸内海中央部において，本種の産卵に関する研究を行ない，次の結果をえた. 1) 備讃瀬戸におけるトラフグ漁場は，水深20m以上の比較的潮流の早い場所IL 局在している.漁期は4月中旬-5月中旬であり，産卵群を漁獲の対象としている.従って，これら漁場は同時にトラフグの産卵場である. 2) 産卵群の形態的特徴を明らかにした.タイ縛網に混獲される産卵群の性比は，雄3:雌1の割合であった.全長平均値閣の雌雄差は認められなかったが，体重平均値聞にみられる両者の差は極めて有意であり，雌が大きい. 3) 卵巣内における卵の発達は，一様に進行する.とのζ とから，放卵は一回あるいはきわめて短期間に完了するものと推定される. 4) 字卵数(N) と全長(L，mm) および体重(W， g) との関係は，それぞれ次の指数式で表わすことができる。 N=0.0000312・L3.862; N =0.0120W1.161. 5) トラフグ漁場の底質中より，天然に産着された多量のトラフグ卵の採集に成功し，産卵場を確認することができた. 6) 産着卵数と底質の粒子組成との聞にみられる関係から，産卵床の特徴を明らかにすることができた.卵の最も多く見出された場所は，径2-4mmの粒子の卓越する(重量組成)場所であった.底質が細砂，粗様よりなる場所からは，殆んどあるいは全く産着卵は採集できなかった.

Studies on the Fish Oils (from Fish) caught in the Inland Sea of Japan. I.

1. Harengula zunasi oil.Yellowish brown oil was obtained at yield of 6.95% from Harengula (Bleeker), the characteristics of which were as follows : d154 0.9233, n20D 1.4758, A.V. 12.3, S.V. 192.4, I.V. (Wijs) 168.1Unsaponifiables 1.34%.Solid acids were chiefly composed of C16 acid with range of C14-C22. Liquid acids contained considerable amount of C18, F2 acid and were composed of C12-C22 acids of F1, F2, F3 and higher unsaturated acids. Unsaponifiable matter, a pale yellow lamina, had mp 129131°C and I.V. 129.4, and existence of considerable amount of cholesterol was recognized.2. Saurida oil.Sauride argeyrophanes (Richardson) contained 0.73% of body oil. The characteristics of the oil and those obtained from the fish organs were as follows : d154 n20D A.V. S.V. I.V. (Wijs) Unsap. matter ColorBody oil 0.9391 1.4828 19.0 192.2 195.4 4.13 Reddish brownEntrails 0.9304 1.4875 106.9 159.6 183.5 17.09 Dark brownLiver 0.9240 1.4790 73.8 182.3 167.5 9.15 Reddish brwonSolid acids of body oil contained most of C16-C18 acids, and C14 and C20 acids also existed. Liquid acids were composed of F1, F2, F3 and higher unsaturated acids. Unsaponifiable matter of the oil had the following characteristics : Yield% I.V. mp (°C) Color reaction with conc. H2SO4Body oil 4.18 114.2 124128 Reddish brown (-) Entrails oil 17.08 116.8 124128 Reddish brown (+) Liver oil 9.15 128.6 Reddish brown (+) Cholesterol seemed to be main component of the matter.3. Half-beak oil.The oil prepared from Tylosurus gigantcus (Temminck & Schlegel) had the following characteristics : Yield% d154 n20D S.V. I.V. (Wijs) Unsaponifiables %0.69 0.9235 1.4817 158.0 160.4 12.79Solid acids contained most of C16 and C18 acids, and C14 and C20 acids also existed. Liquid acids were composed of F1, F2, F3 and higher unsaturated acids. Unsaponifiable matter had I.V. 116.7 and mp 134.2138.5°C, and cholesterol seemed to be main component.

Studies on the helminth fauna of Japan. 57. Nematodes of fishes. III.

It is my greatest pleasure and honour to contribute a part of the series of my studies on the helminth fauna of Japan in honour of Professor R. T. Leiper, one of the most distinguished helminthologists in the world. The material on which the present paper is based was collected at the Tamano Marine Laboratory of Okayama University on the Inland Sea of Japan except for a new species of Raphidascaroides which was taken by Mr. T. Yamamoto at the Marine Biological Laboratory, Kyoto University, on the Pacific coast of Wakayama Prefecture. Acknowledgments are due to the staff of the Tamano Marine Laboratory and also to Mr. Yamamoto for their generous supply of the material.

日本近海産ウシノシタ魚類の分布-I

In this paper, the zoogeographical distribution of the Japanese soleoid fishes has been quantitatively investigated. The faunal characteristic of this group of fish at various representative localities extending from Japan to its adjoining region is first analysed by making use of SCHENCK et KEEN' method. The central latitude of each sole is represented by the mean velue of the northern and southern limits expressed by the geographical latitude. The biological latitude of each representative locality is the mean of the central latitudes of several species found there. The latitudinal change of the distributional index (D•1), which is the difference between the geographical and biological latitudes, is described as the faunal characteristic of each locality. The results obtained in this study are summarized as follows: 1. Based upon the central latitudes, the Japanese soles are made up of 3 forms, tropical, subtropical and temperate. Thus, the fish of which the central latitude is lower than 20 is called herein tropical form, which is represented by 7 species in Soleidae and 3 ones in Cynoglossidae. The subtropical form, defined here as one of which the latitude is about 30, contains 2 species in Soleidae and 5 ones in Cynogrossidae. The remaining 2 species of each family belong to the temperate form, of which the latituds is always higher than 33 (Tab. 1). 2. The latitudinal change of D•I in the Japanese soles found from Singapore or Kai to Muroran Prov. of Hokkaido or Uladivostok seems to be rather gradual, except for sudden change which takes place between Owashi (Mie Pref.) and Numazu (Shizuoka Pref.), and Hainan and Amoi, respectively (Fig. 2). 3. The point where the value of D•I becomes 0 is found to exist in latitudes 22°N in the Pacific and 27°N in the China Sea.

トリガイの生態学的研究-I

A study on growth of Fulvia mutica (REEVE) from Suo-dada, Inland Sea of Japan was carried out. The results are as follows: (1) Ring formation of shell of this bivalve seems to take place once in a year, during the months August-January in the first ring, and April-January in the second and other ones. Causative factors for ring formation appear to be water temperature and physiological rhythm of spawning. (2) Shell-length becomes about 69mm., 85mm. in one and two full age respectively. In shells of ages more than three, shell-length is above 85mm.

瀬戸内海におけるマダイ資源について

It it often said that the fishing grounds have been laid waste all over the Inland Sea of Japan because of overfishing …… especially in the situation of Porgy Pagrosomus major ( T. & S.) fishery which is one of the most important in her waters. The writer attempted to argue and analyse the Porgy population, from the past records of catch and the fishing vessels with reference to the survival rates measured in 1937 by Y. WANG and in 1949 by the writer and his assistants, so as to make the nature of its population clear. The trends of yearly yield in each prefecture facing the Inland Sea, are claseified into two types (Fig. 1) by analysing the secular variations, in regarding them as vectors and time series. The survival rates are estimated to decrease from 0.82 in 1936 to 0.64 in 1949 (Tables 4, 6 and Fig. 8) for about ten years. It seems that the decrease has been. caused by strengthening fishing effort, represented in the number of fishing vessels. In Tables 7 and 8, are shown the rates of natural mortality, fishing mortality, survival and exploitation of three prefectures respectively, calculated from competitive relation between the fishing mortality rates and the fishing efforts. The thick full lines, as shown in Figs. 11, 12 and 13, represent the actual fluctuations of catch. The other four lines indicate the relative variato ?? of reconstructed catch, computed from the estimated values of the above-described population parameters under four trials. Considering the lines of recontructed catch and the actual one, the writer concluded that the number of 5-10 tons vessels is reasonable to show the fishing efforts. Because the catch has not grown larger in spite of the annual increase of exploitation rate, the abundance of population is considered to be reduced by half for about past ten years : evidently it is a dangerous state of overfishing. Thus the optimalized fisheries or the regulation of fishing are inferred in Tables 9, 10, 11, and 12, concluded from C-f diagram (Figs. 14 and 15). The prediction of catch has been able to practise in three ways: namely ……the correlation (Tables 13, 14 and 15) between the catches and the environmental factors, the reconstruction (Figs. 11, 12 and 13) from dynamical relation among the population parameters, and the extrapolation (Figs. 16 and 17) d ?? d ?? ced statistically from the correlograms (Figs. 6 and 7) of the secular variations of catch.

トリガイの生態学的研究-II

The results of the present investigation on a bivalve, Fulvia mutica (REEVE) from Suo-nada, Inland Sea of Japan are as follows: (1) This shell has two spawning seasons in a year, viz., February-June, and August-Nove-mber. April-May and September-October are in heigt of the spawning season respectively. (2) This animal is a hermaphorodite. (3) Sexual maturity seems to be reached one year after hatching, and the biological minimum size is about 3.8cm. in shell-length. (4) Sexual castration is found to exist in those individuals having cercaria parasite: in the gonad of such shells, no ovary is found. A few spermatozoa present. (5) Mature eggs measure 110μ and 75μ in longer and shorter diameter respectively. Spermatozoa about 60μ in overall length.

The Protection of Fur Seals in the North Pacific Ocean

The fur seals of the North Pacific comprise three distinct herds, which do not intermingle in any way, having distinct breeding grounds, feeding grounds, and routes of migration. By far the most important of the three herds is that which resorts to the American Pribilof Islands. This herd breeds upon the islands of St Paul and St George during the summer, and in winter passes down through the channels of the Aleutian Islands into the Pacific Ocean. The migration reaches as far south as the coast of southern California and returns along the west coast of North America. The next herd in importance is that resorting to the Russian Komandorski (Commander) Islands. This breeds upon the islands of Beringa and Medni, passing in winter down along the eastern coast of Japan and returning by the same route. The third herd is resident in the Sea of Okhotsk on the Japanese Robben (Kaihyoto) Island, where a considerable remnant still exists. It formerly occupied other rookeries on four islands of the Japanese (formerly Russian) Kuril (Chishimi) group, but these are now virtually extinct. The migration route of this herd lies in the inland sea of Japan.

LV.—The Perciform Genera Gymnapogon and Nannatherina

YMN.POGON japonicus, a new genus and species of fishes, was described by me in 1905 (Regan, Ann. Mag. Nat. Hist., (7) 15: 19) from a number of specimens measuring up to 45 mm. in total length, from the Inland Sea of Japan. I considered it to belong to the Chilodipteridae (=Apogonidae), and using Jordan and Snyder's review of the Japanese fishes of this family (Proc. U. S. Nat. Mus., 22, 1901: 891-913), I put it near Telescopias, which it appeared to resemble in having the spines feeble, canines anterior in the upper jaw, and lateral in the lower, preoperculum produced into a thin flap, etc. In 1913 (Classification of the Percoid Fishes, Ann. Mag. Nat. Hist., (8) 12: 111-145) Telescopias, as a synonym of Scombrops, was placed in the Pomatomidae, and Gymnapogon was mentioned as related to it. I have for some time thought it likely that this was a mistake, but it was not until I had read Herre's description of Henicichthys philippinus (CoPEIA (4), 1939: 200), evidently a Gymnapogon, that I decided to reexamine the types, and to study the skeleton. This I have done by examining an alizarin preparation and by dissecting another specimen. Henicichthys foraminosus Tanaka, 1915 (Tomiyama, Japanese J. Zool., 7 (1), 1936: 50, fig. 9) is a synonym of Gymnapogon japonicus. Tomiyama's figure is good, except that the pectoral fin is too high, and the caudal rays are too divergent. He considers this fish to be a gobioid, but it differs from all known members of this group in having the gill membranes separate and two anal spines, and I find that the skeleton is typically perciform. In most respects Gymnapogon japonicus resembles the Chilodipteridae, especially Chilodipterus, but it differs from them in the following characters: No scales; sides of head with a network of series of small pores; 20 or more vertical series of similar pores on each side of body; lateral line represented by a series ending below soft dorsal, and another on middle of side of tail. Fin spines very slender. Pectoral higher, the upper end of its base about equidistant from dorsal and ventral profiles. Operculum connected by membrane to pectoral arch, the gill opening ending a little above the pectoral. No supramaxillary (or supplemental maxillary). There appear to be no other differences from the Chilodipteridae. The dentition is similar to that of Dinolestes and Synagrops. The preoperculum, produced backwards below as a large thin flap, is also much as in these genera. The dorsal fin has VI, I 10-11 rays, the anal II 9-10. The caudal has 17 principal rays, 15 branched, and a series of about 10 procurrent simple rays above and below, a structure approached in Synagrops. The pelvics, with I, 5 rays, are close together, a little in advance of the pectorals, which have 13 or 14 rays. The pectoral fin is supported by four hour-glass shaped radials. The skull is essentially similar to that of Dinolestes, as described by Starks (Proc. U. S. Nat. Mus., 12, 1899: 113-120, pls. VIII-XI), but with parietal crests scarcely developed, and with a short ethmoid region, ending

眞鯛の系統に關する研究

Pagrosomus major, obtained outside Inland Sea of Japan, viz. in Prefs. Wakayama and Tokusima, is entirely different in stock from that caught inside it. The annual ring of scale of the fish seems to be formed in February to early March, the season of the lowest water temperature in the sea region in question.

瀬戸内海に於ける鯛の漁況

Based on the yearly records, the relations among the catches of sea-breams from various waters both inside and outside the Inland Sea of Japan, and the relations among the catches and the meteorological factors in the main fishing seasons, were investigated statistically.

39. Odontoma in a Fossil Elephant from the Inland Sea of Japan

39. Odontoma in a Fossil Elephant from the Inland Sea of Japan

瀬戸内海に於けるマグヒのStockに關する一二の知見

On the basis of analysing the materials landed at the Fish Market of Hirosima City, some nature of the stock of Pagrosomus major fished in waters of Setonaikai, the Inland Sea of Japan, was studied.

Odontoma in a Fossil Elephant from the Inland Sea of Japan

The Specimen, a fragment of the right horizontal ramus of the mandible containing the first, second, and thrid molars, was dredged from the sea bottom off the Island of Kotuti, Kagawa Prefecture in January 1933., It is now preserved at Waseda University, Tokyo., The mandible is broken at tha anterior margin of the first molar, the ascending ramus and the inner and lower sides of the horizontal ramus being also damaged., Palaeopathologically speaking, a number of intresting features are observed in this specimen., First, a compound odontoma of the first and second molars has taken place, which is a benign tumor derived from an abnormal arrangenment of dentine, enamel, and cementum and a sporadic calcification in tooth development., Second, a great hypertrophy of the right ramus has happened, which has given rise to a bulbous appearance to the jaw., Third, the concavity of the diseased molar is greater than that of a normal molar., Fourth, the breadth of the former is one-and-a-half times that of the normal., And fifth, the enamel figure on the friction surface of the anomalous molar is irregular as shown in the plate., The third molar, which now contains the anterior talon and twelve ridges, has lost 4-8 ridges and the posterior talon., Its grinding had not yet begun The maximum length of its crown is 180 mm., and its width at the sixth ridge 60 mm., The height of the crown is 128 mm., at the fifthe ridge, and 132 mm., at the tenth., The frequency of ridges in a standard length of 100mm is 6., 5., For reasons given above it is almost impossible to determine its specific name, but the writers believe that it may belong to Palaeloxodon namadicus (FALCONER and CAUTLEY), the well known Pleistocene elephant., Finally the writers wish to express their thanks to Professor Tosikazu Tokoro Nippon Dental College, for dental information received.,

眞鯛の成長に就て

The age of 56 specimens of a teleost, Pagrosomus major T. & S., collected from Mito (Pref. lbaraki), Tyosi, Bosyu, and Misaki was determined by reading off the number of the annual rings of the scales, and it was found to range from 1 to 26 years. More or less variable in various characters as they are, the material at my disposal may be recognized as representing one category. It appears that the material from these localities are slower in growth than the same species of the fish caught in Inland Sea of Japan. The reader is referred to the accompanying figures for further details.

XI. On a Collection of Crustacea, Decapoda and Stomatopoda, chiefly from the Inland Sea of Japan; with Descriptions of New Species.

XI. On a Collection of Crustacea, Decapoda and Stomatopoda, chiefly from the Inland Sea of Japan; with Descriptions of New Species J. G. de Man J. G. de Man 1Ierseke (Holland) Search for other works by this author on: Oxford Academic Google Scholar Transactions of the Linnean Society of London. 2nd Series. Zoology, Volume 9, Issue 11, March 1907, Pages 387–454, https://doi.org/10.1111/j.1096-3642.1907.tb00453.x Published: 09 April 2009

LIV.—Diagnoses of five new species of Decapod Crustacea and of the hitherto unknown male ofSpirontocaris rectirostris (Stimps.)from the Inland sea of Japan, as also of a new species ofPalæmonfrom Darjeeling, Bengal

LIV.—<i>Diagnoses of five new species of Decapod Crustacea and of the hitherto unknown male of</i>Spirontocaris rectirostris (<i>Stimps</i>.)<i>from the Inland sea of Japan, as also of a new species of</i>Palæmon<i>from Darjeeling, Bengal</i>

An Atmospheric Phenomenon in the North China Sea

DURING a recent wintry cruise in H.M.S. Caroline in the North China Sea, a curious phenomenon was seen which may be of interest to your readers. The ship was on passage between Shanghai and the western entrance of the famous inland sea of Japan. On 24th February, at 10 p.m., when in latitude 32° 58′ N., longitude 126° 33′E., which, on reference to the map, will be seen to be sixteen to seventeen miles south of Quelpart island (south of the Korean peninsula) some unusual lights were reported by the officer of the watch between the ship and Mount Auckland, a mountain 6,000 feet high. It was a windy, cold, moonlight night. My first impression was that they were either some fires on shore, apparently higher from the horizon than a ship's masthead, or some junk's “flare up” lights raised by mirage. To the naked eye they appeared sometimes as a mass; at others, spread out in an irregular line, and, being globular in form, they resembled Chinese lanterns festooned between the masts of a lofty vessel. They bore north (magnetic), and remained on that bearing until lost sight of about midnight. As the ship was passing the land to the eastward at the rate of seven knots an hour, it soon became obvious that the lights were not on the land, though observed with the mountain behind them.