The writer attempted to reinvestigate the plant environments from the microclimatological. stand point of view, and first the relation between leaf temperatures under natural condition and the environmental elements was studied. Leaf temperature and the environmental elements such as air temperature near the leaf, surface temperature of soil, solar energy(by GORZINSKY's solarimeter), and wind velocity(by hot-wire anemometer)are recorded simultaneously, employing new type self-recording galvanometer. For example, leaf temperature of some alpine plants and of sand-dune plants, leaf temp. of tea-plant at the time of frost formation, leaf temp. in and out of the shelter at orange orchard, and leaf temp. at the rice-field under the special environment, were reported.

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1) Dr. PAVLYCHENKO (1949) advocated the heavier seeding, cross seeding, post seeding cultivation, and so on as biological methods of weed control. Since 1949,the authors have studied methods and mechanisms increasing competing power of crops, particularly Oryza sativa L. var. terrestris MAKINO (Okabo in Japanese name). Some field experiments in 1952 testing the weeding effects to the increment of yield of Okato were reported here. 2) The field experiments were done by means of the latin square of five treatments. Treatment A is perfect weeding, B is non-weeding, C is weeding a month after seeding in May 19th, 1952,D is weeding a month and a week after seeding, and E is weeding a month and two weeks after seeding. Such treatments were based on the preliminary experiments in 1951,resulting the damage of weeds to Okabo when they were not smothered more than a month after seeding. 3) The dispersion of weeds is related to the desing of experiments and the mode of dispersion was tested by the senior author's coefficient of homogeneity (NUMATA 1949). In spite of the seedling stage (cf. CURTIS and McINTOSH 1950), they distributed considerably at random (Table 1), perhaps because of the full disturbance of the surface soil in the crop field. The dominance-subordination relationships of the weed population were represented by the relative density and the relative weight (Table 2,3). Especially in the weight, a significant difference was demonstrated between the growth of weeds of D and E. That is, the weed population grew remarkably after June 26th (D)(Table 4). The biological spectra of weed population indicate the steady increment of the grass form and R_5-type like Digitaria sanguinalis var. ciliaris in sharp contrast to the broad-leaved and R_5'-type weeds (Table 5). 4) The average yield of each treatment is different significantly with one another by the analysis of variance (Table 6), especially E is different significantly to A, C. and D (B is out of the question because of non-harvest). Then, the time after D will be in the critical condition for Okabo. The variation of the number of leaves reflects the same state of affairs (Table 8,9). The order of the average number of leaves was reversed after June 26th (D). From these data as a weed-crop population, it nessesarily follows that the weeding for Okabo should be done before D treatment, and the weeding effect after that time will become very small.

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A clay bed including plant remains, situated in the suburbs of Kochi city was studied Palynologically. As the results of pollenanalytical studies, this bed shows a dominance of conifer forest throughout. While the deciduous broad-leaved trees are of less important and tends to decrease upward. The floral composition shown in this bed is similar to that of the present community at the height of about 800-1000 m in this district. From this fact it may be inferred that this bed was deposited in cooler and wetter climate. The age of deposition seems to be younger than that of Pliocene beds already published by Nakamura. (1951,1952) But more detailed correlation of this bed still remains for the future when many more analytical results have been obtained.

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The algae and other organisms growing on the belt transect established on an inclined rock surface on the coast of Yoshimi, Yamaguchi Pref., were all denuded in March, 1952. In the same season of the following year, the comparison of newly grown algal communities with the adjoined untreated ones on the same rock surface was carefully made by means of degree of cover and measure of frequency. The obtained results are summarized as follows : 1) The zonal arrangement in the adjoined vegetation is as below : [table] These zones are comparatively distinct. In the newly grown vegetation, however, the zonal arrangement has become indistinct, since almost all the species growing in the upper littoral belt(e. g., Gloiopeltis, Scytosiphon, Endarachne, Sargassum Thunbergii, Cladophora, etc.) are inclined to descend to the lower levels thus mixing together and these zones become very wider. 2) Corallina pilulifera, an erect-perennial alga, is the most dominant species in the lower zone of the adjoined vegetation. In the newly grown population, on the other hand, the crustaceousannual algae (e. g., Petrospongium, Ralfsia, Melobesiae etc.)have become conspicuous as dominant species.

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In this paper the rangse of two species of mosses are treated. 6. Pterobryum arbuscula Mitt. Pterobryum arbuscula belongs to one of the most remarkable epiphytic mosses as is commonly found in the primeval foreset in Japan. At present Pt. arbuscula is known from 137 localities, viz. 1 in Hokkaido, 3 in N. E. Honshiu, 23 in M. Honshiu, 47 in S. W. Honshiu, 28 in Shikoku and 49 in Kiushiu. So far as the present state of our knowledge is concerned, this species has its northern limit at Oboro (43°03′L.N.) in Hokkaido and its sourthern limit in Yakushima (30°15′L.N.). The Macrofrequency of this species in each district is shown in table 5. As will be seen from map 6 and table 5,the centre of the distribution seems to exist in Shikoku and Kiushiu. According to my knowledge, its highest elevation lies in Mt. Yatsugatake ascending to 1820 m. above sea level and its lowest elevation lies at Oboro, Hokkaido, descending to 40m. above sea level. Area geogr. Endemic to Japan. 7. Theriotia lorifolia Card. The genus Theriotia was established by CARDOT in 1904,based upon the sterile specimen which was collected by FAURIE at Quen-San in Corea. CARDOT in his paper put this genus belonging to the Calymperaceae, suggesting that it represents a peculiar structure of the leaves. BROTHERUS afterwards (1909&1925) removed it into the Diphysciaceae, as closely allied to the genus Diphyscium. The genus is monotypic and the habitat of this plant is of unusual interest, because the plant is only found at wetty or submerged silicious rock-bed. At present Th. lorifolia is known from 61 localities, viz. 7 in M. Honshiu, 40 in S. W. Honshiu, 4 in Shikoku, 8 in Kiushiu and 2 in Corea. So far as our present knowledge goes, this plant has its northern limit at Quen-San (39°10′L.N.) in Corea and its southern limit in Yakushima (30°15′L. N.). [table] The macrofrequency of the species in each district is shown in table 6. As will be seen from map 7 and table 6,the centre of its distribution lies in S. W. Honshiu. According to the present knowledge, this plant seems to be one of the Japamurian species), its highest elevation lies at Mt. Ishizuchi ascending to 1640m. above sea level and its lowest elevation at Miyajima descending to 60 m. Area geogr. Endemic to Corea and Japan.[table]

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Miura Peninsula is a highly civilized district near the industrial and commercial center of Tokyo and Yokohama. The forest climax is now repersented by only fragmental stands in the grounds of shrines or temples. From the vegetational survey of those fragments the associations were determined by their floristic composition, and the area of each association was reconstructed on a map. On the coastal escarpment of sandsone and shale, we can find Pittosporum Tobira-Euonymus japonicus association, while on the stabilized sand. Machilus Thunbergii-Polystichum japonicum association is formed as a climax stand. The territory is stretched into the inner part of the peninsula along the valleys. The highest peak, Mt. Oogusuyama is 241.7 m. high above the sea-level. The lowland hils constructing the body ground of the peninsula is the climax area of Shiia Sieboldi-Bludhia japonica assocaition. Only the Zinmuzi stand belongs to the typical Maesa subassociation. The rest stands together with those of Awa Province facing to Tokyo Bay are included in a newly described subassociation, Bladhieto-Shiietum fatsiosum SUZ.-TOK. et TANIGUTI (Differential species Fatsia japonica and Gilibertia trifida).

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(3)Forest communities and forest zones in the northern range of Abies fuma. The plant sociological studies of the stable forest communities in the vicinity of Ichinoseki, Iwate Prefecture, show that in the plains the climax forest is the Abies firma-Fagus japonica-Pleioblastus chino community, whlie in the hills higher than 100 m. above the sea level it is the Fagus crenata-Abies firma-Rhododendron japonica community. The northern limits of the former climax community, whose typical structure was shown in the previous paper, fall approximately on the prefectural border between Miyagi prefecture and Iwate prefecture(about39°N.). This community stretches southward to the northern limits of the evergreen forest occupying the areas between the deciuous, and the evergreen, forest zone chiefly in the Pacific side. In the warmer districts the coniferous forests, chiefly composed of Abies firma and Tsuga Sieboldii and similar in structure and physiognomy to the Abies firma-Fagus japonica-Pleioblastus chino community of the present work, occupy the areas on the sides of the mountains, and between the evergreen forest zone and the decidous one. A zone which includes these coniferous forests, be it horizontal or vertical, may be said to be the Abies firma forest zone. It is not so characteristic as evergreen, and deciduous, forest zone, so much so that it may be regarded as a transition zone between them.

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