(1) The forest vegetation on Mt. Tsurugi, Shikoku can be divided into two zones, viz., the deciduous forest zone (1200-1700m above sea-level) which is dominated by Fagus crenata climax forest, and the subalpine coniferous forest zone (above 1700m above sea-level) mainly occupied by Abies sikokiana climax forest. (2) In the deciduous forest zone Fagus crenata-Sasamorpha purpurascens association is developed as a climatic climax. The community dominated by Pterocarya rhoifolia, Acer mono var. eupictum, etc. is found along the streams. Tsuga sieboldii community and T. diversifolia-Pinus mayri community occur on shallow soils or rocky outcrops as the edaphic climax. Quercus crispula community is a secondary forest developed on the open area and migrates gradually into the Fogus crenata climax community. The pure forest of Abies homolepis is often found in the upper part of this forest zone. (3) The climatic climax forest of the upper part of the subalpine coniferous forest zone is Abies sikokiana community, and this community can be divided into two types, Abies-Sasa sociation and Abies-Bryophyta sociation. Tsuga diversifolia community occurs in the lower part of this forest zone. Betula shikokiana community represents a secondary forest throughout this forest zone.

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The distribution of coralline spores was surveyed in relation to the situation of mother communities in Nabeta Bay. The communities dominated by Amphiroa ephedraea lay at about 3 m of depth in two rows along east and west sides of the bay. Spores were trapped by means of submerged slides regularly placed at various depths and distances from the mother community. When counted after 9 days, on the west side community, frequency of spores decreased, as a general rule, according to the distance from the community either in vertical or horizontal directions. But the details of variance, shown in Fig. 2 as an isogram, indicated that the decrease towards the sea level was steep just above the community, while it was more gradual at distant places showing the frequency maxima at the depths nearer to the surface. A survey of the whole area after 7 days, shown in Fig. 3,indicated that the frequency was greater at the surface than the bottom near the entrance of the bay. The variance was rather irregular on the east side as compared with the west side due to complexity of the community formation. The spore counted was zero at several points in the middle of the bay.

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1. I made this report on the vertical distribution of the plants of Mt. Ashitetsu which lies in the central part of Hokkaido. 2. The followings are assumed to be the vertical distribution regions on Mt. Ashibetst. A. Deciduous broad leaved tree region (300-500m). B. Ever-green conifer region (500-800m). C. Betula region (800-1400m). D. Higher shrub region (1400-1700m). All over the whole mountain Sasa senanensis is most dominant and is the main element in composing the third layer. Owing to the rapid invasion of S. senanensis after the opening of tree crowns, the succession of the tree is unfavorable. Though Picea jezoensis and Abies sachalinensis are the chief trees in Ever-green conifer region, deciduous broan leaved trees are so mixed that this region might be called mixed forest region. 3. Upon my investigation, it is revealed that the successive diminishing quotient of the earth temperature is 0.41℃ on Mt. Ashibetsu, e.g. in July and August on this mountain, the earth temperature is assumed to diminish 0.41℃ on average per 100m higher.

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In this paper the range of one species of hepatics is treated. 8. Plagiochila yokogursis Steph. Plagiochila yokogurensis belongs to one of the most remarkable endemic hepatics and is commonly found as epiphytic on the barks of trees or rocks in southern part of Japan and Corea. At present Plag yokogurensis is known from 70 localities (32 of which are hitherto known already and 38 are newly added in this paper), viz. 11 in Middle Honshiu, 18 in South-West Honshiu, 12 in Shikoku and 28 in Kiushiu and 1 in Corea. So far as our present knowledge goes, this plant has its northern limit at Mt. Izurukwanon (36°28'L. N.) in Tochigi Prefecture and its southern limit in the Cape of Sata (31°06'L. N.). The macrofrequency of this species in each District is shown in table 7. As will be seen from map 8 and table 7,the centre of its. distribution seems to exist in S. W. [table] Japan. As is seen in table 7,the densities of Plag. yokogurensis in 4 districts of Japan are arranged in the following order : Kiushiu>Shikoku>S. W. Honshiu>M. Honshiu. But the distribution-fall^<1)> is not seen between them. According to the present knowledge, this plant seems to be one of the Japamurian species^<2)>, its highest elevation lies at Mt. Akaishi ascending to 1060m above sea level and its lowest elevation at Wakayama city descending to 5m. Area geogr. Endemic to Japan and Corea.

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