1. Ôcho Village, located on Osaki-shimo Island in the inland sea of Setouchi, is known as a village most specialized in citrus culture in Japan. The ratio of orchards to the total arable land was 97% in 1929. During the war, 20% of the fruit trees were cut down. And by 1950, the ratio had again increased up to 90%. Before the springing up of citrus culture in the village, villagers were growing peaches. In 1859, UNSHU tangerine was introduced to the village. Early-crop (Wase) UNSHU tangerine was introduced in 1903, which at present. occupies 55% of the total amount of citrus crop in Ôchô. This is of the highest as the rate of early-crop UNSHU in Japan.
2. The area of Ôchô Village covers a sloping land of 10 to 40 degrees. Thecitrus trees are planted in terraced fields, 70% of which have stone-steps and. 30% soil-steps. To carry the fruits down the steep slope, a simple cableway was set up in 1921. Today, there are 46 cablecars, in the village, by which 30% of the total crop of tangerines are carried down the slope. The entire cable system is operated by electricity and under the management of the cooperative of the villagers. There is no comparable example to this scheme in Japan.
3. Canned tangerine was first made here in Japan in 1927. The markets for Ôchô tangerines are Kôbe-Osaka area (40%), Tôkyo (30%), and others. Marketing of the early-crop UNSHU is made in October, 35%; November, 50%; December, 15%. The ordinary UNSHU is shipped in November, 10% December, 30%; January, 15%; February 20% ; March, 20%; April, 5%.
4. One of the characteristics of citrus culture in Ôchô is the “watarisaku” (farming over the water). Out of 700 cho (1 cho _??_ 1 ha.) of citrus orchard belonging to the villagers, 300 ch5 is located within the village and 400 cho is scatteringly distributed in 30 other villages, namely in many other neighbouring islands. They maintain their “farming over the water” by 200 nonpowered boats and 350 powered boats. The followings are considered to be the factors in bringing up an unusual manner of farming as this.
(1) Limited area of land and increasing population. (2) The sea is calm even in winter, so ferrying by small boats to the orchards in other islands is made without danger. (3) The village of Ôchô embraces a good natural harbour, which enables several hundred boats to be at anchor at one time. And as the harbour faces to the east, it is shielded from the north-west winter monsoon. (4) As the land is limited in area, its price is high. If one sells 1 tan (1/10 cho) of upland fields in Ôchô, he will be able to purchase 5 tan of uplandfields or even more of forest in Ehime Prefecture. (5) There are customs of establishing “branch families” and of “inheritance by the youngest child” in Ôchô. The eldest son and the younger ones, got mnarried, buy orchards outside the village, and settle there. The younger children stay in their native house and engage in fruit-growing, instead of becoming fantory workers as is usually the case in other farm areas. (9) They traditionally have skilled techniques in fruit-growing. The general standard of techniques has been high. The villagers are industrious and have no political disputes. The present village master is the third one since 1889. (7) The successive, village masters encouraged the farming over the water. The Hiroshima Agriculture and Industry Bank had actively assisted the farmers in purchasing farmland, loaning to them over one million yen since the end of the Meiji, era. Due to the recent inflation, all the loan has been returned, and thevillage is prosperous. (8) Citrus growing has the highest possibility of cash income. Industrial processing of the products is developing, and the enterprise, is economically stable.

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When I made a study on the alluvial plains of Japanese Inland sea, Setonaikai, I perceived that the depth to the basal gravel bed beneath the delta plains corresponded to the river system of the period of the lower sea-level. So I tried to trace the surface of the gravel bed in the bottom of that sea, to inquire into the time when it took shape and to restore the river system to the original state. For these purposes Im de an analysis of its marine topography.
(1) Its topography is very complicated, but generally it is divided into two. One is called Nada (open sea). Judging from the accumulative depth percent of Nada (Fig 2) we can find the fact that the depth of each part already corresponds to the river system. But in this case, we cann't estimate its true depth for continuing of heterogeneous mud deposition.
(2) The other is called Seto which is composed of straits, which have many corraded topography as caldron (Fig 3• 5•7) So we know the depth its surface there. Its depth is deeper than that of mud and shallower than the maximum of gravel in chart. (Fig 6)
Using the result of these observations, we can trace its surface in a state of considerable stretching from delta to the occean. In view of the results so far achieved, I grasped the following facts:
(3) The gravel surface of delta and caldron, and continental shelves of occean lie on the same topographical surface in the period of lower sea-level which seemes to be of Würm ice stage:. (Fig 8•9)
(4) There is a drowned valley in the bottom of Nada where homogeneous deposition continued (Fig 10). The drowned and burned river system is estimated as Fig 11. According to these facts Setonaikai resembles the Sunda Sea concerning the topography of the shelves. The difference is that in the latter there are such islands as Bangka and Billiton.
(5) It is conjectured that in this period there must have been slight and local climatic topography for its surroundings.

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本論文では，日本を中心とした東アジアの海底産の第四紀哺乳類化石の産地と産出化石について，公表されているデータをもとに，その概要をまとめた．化石産地の主なものには，根室海峡，山陰沖の日本海，渥美半島沖，瀬戸内海，有明海，東シナ海の大陸棚東縁，黄海北部と渤海，中国の台湾海峡沿岸海域，台湾の澎湖水道がある．まとめた概要をもとに，化石の大部分を占める陸棲哺乳類について，その特徴や時代を議論した．そのような化石には，アケボノゾウ，トウヨウゾウ，ナウマンゾウ，ワイガゾウ，マンモスゾウなどの長鼻目や，シカ科（偶蹄目）のものが多い．化石産地のうち，瀬戸内海の化石には，更新世の様々な時期のものがあるが，他の産地の化石は，後期更新世のものが大部分と考えられる．東アジアの化石産地や産出化石を，世界の代表的な産地である北海のFlemish Bightのものと比較した．

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