The plant sociological studies were done on the forests of Abies, firma-Fagus japonica climax zone in the suburbs of Sendai. Six different types of forest were distinguished in the zone : (1)Abies firma-Fagus japonica-Pleioblastus chino, (2)Abies firma-Quercus serrata-Castanea crenata, (3)Abies firma-Aucuba japonica-Bladhia japonica, (4)Quercus serrata-Castanea crenata-Pleioblastus chino, (5)Quercus serrata-Castanea crenata-Miscanthus sinensis and (6)Pinus densiflora-Quercus serrata-Pleioblastus chino community. Of these communities Abies firma-Fagus japonica-Pleioblaslus chino community is the climatic climax restricted nowadays to unmodified lands and other five are the secondary ones degenerated from the climax chiefly by the human activities. The structure and successional trend of each community were studied in detail and the mutual relations among the communities were also concluded.

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1. As the result of a synecological survey of the epiphyte communities of lichens in the subalpine forests of Titibu mountain region, some 1600-2400m in alt., the Usnea longissima-Parmelia pseudophysodes, the Alectoria lata-Cetraria pseudocomplicata and the Usnea diffracta-Sphaerophorus Ep. -Associations can be recognized on the barks of Tsuga diversifolia MAST., Picea jezoensis CARR. v. hondoensis REHD., Abies Veiichii LIND. and Abies Mariesii MAST. in the forests of the Tsuga diversifolia-Rumohra mutica-and the Abies Veitchii-A. Mariesii-associations^<3)>. And every Ep.-Association is composed of four or six Ep.-Sociations which are named after the dominant species. 2. An outline of the distributions and developments of every Ep.-Association and Ep.-Sociation here described is explained. 3. The epiphyte communities of lichens in the subalpine forests of the region are highly characterized by the life-forms^<5)> of Ps, VR, Ef and MCf. 4. From the view-point of the life-form spectra of epiphytic lichens, anyone will easily be able to point out a clear difference distinguished between the Fagus crenata consociation of the temperate forests in the Titibu and Iide mountain regions and the subalpine forests of Titibu mountain region.

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The author investigated the xeromorphic characters and drought resistance of mosses, found in different eiviroments around Tottori City. Special attention was given to the relation of drought resistance with osmotic value and protoplasmic permeability to water. It was assumed that the cause of drought resistance of moss is not so much attributed to its morphological or xeromorphic characters as to its plasmatic ones, that is, to the high osmotic value and protoplasmic permeability to water. And in many cases, ILJIN'S theory that "the death of plant cell by drought is caused by the mechanical injuries inflicted on is plotoplasm"is presumablly of little significance in moss.

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1. We studied the structure of plant associations on the creep land in Dainenjiyama, Sendai. This region comprises two geological layers ; the gravel beds(Aobayamalayer)at the upper part, and the tuff beds(Dainenji-layer)at the lower part. 2. This creep land may be divided into 6 blocks from topographic characters. That is ; A-is the barefaced land of clayey soils at soil mass movement. C-is depressed ground between A and D, and is covered with dense vegetation. B-is an old crack ground between A and C, and is covered sparsely with shrubs. D-is the lifted land by soil mass-movement, and is crowded with shrubs and herbs. This block is situated on the front side of C. E_1-is the wall of a small gully. The associations of herbs are seen at the lower wet part where slump from D is laid down. E_2-is restless land on the front side of D, where new cracks are shown and is covered with shrubs. Earthflows are most frequently seen in this place. 3. The successional changes to the original forest(Pinus densiflora-Abies firma association)are found remarkably at the bareland, crack ground and the lifted land, viz. in A, B, E_1,E_2,and D. On the C block the patches of the original forest remain, and a good deal of seedlings and young plants of P. densiflora and A. firma are found there. The structure of the communities in each was analysed one after another in detail. 4. Plant succession on the creep land may be assumed as follow : (table) 5. As the first invaders on this creep land, we can note such plants : Rubus microphyllus, Clerodendron trichotomum, Callicarpa mollis, Miscanthus sinensis, Petasites japonicus, Polypara cordata, Equisetum arvense, Lysimachia elethroides, Polygonum Reynoutria, Lactuca stolonifera.

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1) On this coast, the zonal arrangement of algal communities of the rock surfaces is as follows : (table) The arrangement belongs to the type which is common on the Pacific coast of the south-western region of Japan. 2) Of almost all associations, the upper limit and the width of their zones seem to be influenced by the degree of the wave action. The upper limit and the width have been found higher and wider on surfaces of rocks subject to stronger wave action.

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The area of the present study includes Hokkaido, Saghalien, the Kuriles, the Commander Islands and the Aleutian Islands. The species of Polypodiales growing in the area under consideration attain 99 in total number, the genera 46 and the families 5. Endemic species : Except only one species, namely Polystichum aleuticum which occurs very locally in the middle part of the Aleuian Islands, there is no endemic species. Only two species, namely Polystichum microchlamys and Ctenitis quelpaertensis have their distribution center in the area above mentioned. Disjunctive distribution : Polystichum Lonchitis offers a typical example of disjunctive distribution. The northern limits of the plant distribution are sometimes found in disjunctive lolcalities : for examples of the fern, there are Asplenium incisum in Kamtchatka, Cyrtomium Fortunei, Dryopteris Dickinsii, Lepisorus Onoei in the Island of Okushiri of Hokkaido, Dryopteris laeta in the eastern part of Hokkaido, Dryopteris monticola and Pentarhizidium japonicum in the Island of Kaiba of S. Saghalien. Common species : The common and wide ranging species are Athyrium melanolepis, Dryopteris austriaca and Phegopteris polypodioides. They are all circumpolar elements. Warm temperate elements : As the warm temperate elments, there are Cyrtomium falcatum, Cyrtomium Fortunei, Davallia Mariesii, Dryopteris Dickinsii, Dryopteris lacera, Dryopteris Sabaei, Lepisorus Onoei, Neoniphopsis linearifolia, etc. They occur only in the southwestern part of Hokkaido. Temperate elments : The temperate elements are found in the districts of the southern part from the SCHMIDT'S Line in Saghalien and also of the southern part from the MIYABE'S Line in the Kuriles including Hokkaido. For the area including northern Korea, eartern Manchuria, southern Kuriles and also Hokkaido excluding the south-western part, from the phytogeographical point of view, the writer proposed to delimit an intermediate zone between the temperate Eastern Asia and the Siberian subarctic zone. Subarctic elements : As subarctic elements, there are Athyrium crenatum, Dryopteris austriaca, Gymnocarpium Dryopteris, etc. In spite of the lack of the needle forest, it is very interesting that the common ferns of subarctic elements occur in the northern islands of the present study. In conclusion, the most remarkable character of the region is the sudden decrease of the floral influence of Polypodiaceae of the temperate Estern Asia at MIYABE'S Line and SCHMIDT'S Line.

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