The following results have been obtained by an investigation of the Hirohamatsuna grown in autogeny on some parts of the drained land in Omuta City, in September, 1958. (1)In the middle area, Hirohamatsunas are distributed almost in preference to other plants, and the reeds are distributed around them on the three sides of east, west and south-as if to embrace them. The view reminded one of habitat segregation autogeny of Hirohamatsunas and reeds. (2)From the middle to the bank, a succession of plants seemed to be visible namely, in the middle parts, Hirohamatsunas monopolizingly autogenied in the area, and their growth and frequency was great, but the nearer they were to the bank, the less frequent and grown-up they seemed to be, finally they completely disappeared. According as the Hirohamatsunas were more less frequently seen, the more of the reeds appeared to make their appearance. Further their growth became. better and better until the land was solely occupied by reeds. (3)As for Hirohamatsunas, they make remarkable changes in frequency, growth, and form according to their environments. Frequency becomes greater in the following orders, current coast, sea-water invading area, dry-land area. Their growth rather makes a contrary phenomenon, being in a better state in the current (washing) coast. Therefore, sea-water seems to make great difference to their growth, and yet, it has been found that, the sloping dry land fusing south adjoining, to the current-coast seems to be better-fitted for their growth than the latter. Those grown in the current-coast are slender in form, those in the tide invaded-area thick set, those in the dry-land, neat and small. Being closely(grown)and mixedly grown among others, its twigs are few in number and so their lengths and expansions become less.
The shell speckles of Crassostrea gigas were studied using the shells obtained from Aomori and Hiroshima Bays with special reference to their local variations. The results are as follows. 1. There are various types in speckles on the surface of the oyster shell (Fig. 1,A, B, C, D and E type). All types are found in both of the Aomori and the Hiroshima oysters (Fig. 2), and also at various places in these respective localities (Figs. 3 and 4). 2. The frequency distributions of these types in these two localities are characteristic respectively. Namely the C type (threadlike type) appears most abundantly in Aomori Bay, but B type (bandlike type) in Hiroshima Bay (Fig. 2). 3. The age of the oyster can be judged from the stratifying structure found in the section of the shell and also from the shell weight with which the degree of the disappearing of the shell speckle is parallel (Figs. 5,6,and 7). 4. There is no speckle on the surface of the old shell, and only a few are found inside it. 5. It seems that the longevity of the Aomori oyster is longer than that of the Hiroshima oyster. 6. The pattern of the shell speckle changes with the advance of the shell age, and generally B type (bandlike speckle) occurs in the young oyster and C type (threadlike speckle) in the old oyster (Fig s.7 and 8). 7. In oysters belonging to the same age, the local difference among the occurrence probabilities of various types is not recogaized (Fig. 9) 8. The degree of dissppearing of the shell speckle differs among various habitats in Aomori Bay caused by the difference in the longevity (Fig. 10). From the above, it may be said that in the shells of both of the Aomori and the Hiroshima oysters the bandlike type appears usually in comparatively young oysters and the threadlike type in comparatively old oysters. Accordingly the local variation in the pattern of speckles should be introduced by the local difference of the longevity of the oyster owing to the habitat environment.
In Hokkaido and northeastern regions of Japan Proper, we can find many moorlands, and numerous investigations on the moorland vegetation have hitherto been made. But to our regret, little has been known as to the peat bogs of south-west Japan, especially in Kyusyu proper and the Island of Yaku. Although there are fewer occurrences of moorland in south-west Japan, when compared to those in northern regions, we can find some good examples. Hananoego Bog is the largest one which lies at some 1600m altitude near the wood limit against the uppermost vegetation zone, the zone of Pseudosasa Owatarii. This moorland is surrounded by woodlands consisted of the scrub forest of Juniperus Sargentii, and evergreen shrubs like Rhododendron yakusimanum, Eurya yakusimensis under the canopy of Cryptomeria japonica. It is about 60m long and 40m wide, and its east and west periferies are bordered by two rivulets. The annual rainfall in Yaku Island is tremendous, attaining 4,305mm at Anbo near the seacoast and 8,299mm at Kosugidani 600m above the sea-level. Judged from the vegetational aspect and the experience during the field work, larger amount of precipitation is quite sure at Hananoego, although meteorological observations are lacking. Five lines of peat profiles were observed at 10m intervals, and as the result (Fig. 1) we came to the conclusion that this moorland must have developed by bog formations in several small basins, of which the lowest level with the deepest peat formation was that of the east side of the western rivulet attaining as deep as 1m. The pH-values ranged between 5.0 to 5.4,and the lowest value was measured at Sphagnum papillosum growth. Temperature observed on one summer day reached its maximum at 20cm depth. Several moorland communities were detected there. The Juniperus Sargentii scrub accompanied by Lycopodium and Bazzania is found in cushion-like fragments. They might be the remain of the previous woodlands burled by peat formation. The Sphagnum papillosum bog with co-dominating Juncus Koidzumii and Carex hakonensis presents the optimum phase of peat formation and is developed on the bog-plateau, especially along the rivulet. But in the flat facing to the middle stream of east rivulet, Sphagnum is almost replaced by Rhacomitrium lanuginosum. Rhacomitrium lanuginosum community was probably produced by the colluviation of granite debris, where peat formation is restricted and even surface erosion is prominent here and there. Consequently the moss growth is interrupted by depressions dominated by Eriocdulon decem. florum, and elevations occupied by the dominance of Zoisia japonica. The Campylopus japonicus community occupies the flat of the southern part. Here erosion is completely lacking. The component flora is poor in species, and the peat deposit is not deep. This is assumed to have been formed by the deposition of sand particles and lowering of water table. From the facts mentioned above we can reconstruct the genesis of this moorland. Owing to the high rainfall and flat topography the Sphagnum growth might have started on the slope and the depression covered by Juniperus and in the valley bottom Juncus Koidzumii might have predominantly developed. Thus the peat formation was commenced, but it was frequently disturbed by the deposition of sand. Phragmites and Molinia which are very common in Japanese moorland are substantially absent in this moor.
The forest dominated by Pinus species often builds an edaphic climax, because the occurrence of this plant has some special reference to the petrographic factor. In Central Kyusyu, the two volcanoes, Aso and Kuzyu are adjacent to each other and with Paleozoic formations of the mountain-group of Katamuki-Sobo, thus present a suitable field for the study to elucidate the relationship between the petrographic factor and the occurrences of Pinus-type forest. Lines (Fig. 1) were drawn from the triangular point at the summit of Mt. Katamuki to that at Mt. Kuzyu(AB), and also to the summit of Mt. Neko(AC). These were used as base-lines of huge transects, and plots for actual surveys were selected within 4 sq. km taken at random along the base-lines. The area of the sample plot was(12m)^2 for forest and(5m)^2 for grassland. Within the square, the best developed stand or tree was searched for and observed as the sample. The most predominating type of plant communities other than Pinus-type were also observed in paralell. The subject was approached through four different ways. 1. Seeking after discontinuities in the distribution of species or groups of species along the base-lines. 2. Enumeration of the plant communities in series where Pinus dominates or grows in natural state, and finding of the community which is the most prominent when the area lacks any pine. 3. Growth and vitality of pine. 4. Aspect of the land and its utilization of various grade might be found in the series of sample plots along the basic lines. Among the discontinuities found in any one or more ways above mentioned, those which agree with the border line between two natural vegetational zones must be put aside to detect the special influence of the petrographic factor, and the others which coincide with the exposure of some geological formation are to be picked up. If the discontinuity is traceable in two or more different lines of considerations, it will be more and more powerful. The flora can be classified into six groups, namely, 1. Group of the Pinus densiflora forest, Pinion densiflorae. 2. Group of the montane deciduous forest, Fagion crenatae. 3. Group of the broad-leaved evergreen flora, Shiion Sieboldi. 4. Group of the secondary broad-leaved forest, Castaneion crenatae. 5. Group of the grassland, Miscanthion sinensis. 6. Group of the supra-montane heath, Rhodorion kiusiani. The sample plot AB 12 certainly surpasses the montane zone of Kyusyu and lies in the supramontane zone. Vaccinium Vitis-idaea is a characteristic species of the panboreal class of Vaccinieto-Piceetea and is also dominant in the Japanese subalpine scrub, Vaccinieto-Piuetum pumiae. Miscanthus oligostachyus is the characteristic species of the supra-montane zone of Kyusyu. It should be considered very important that Pinus pumila or the other species of pine or pinaceous family is completely absent in the supra-montane zone of Kyusyu, AB 11 and AC 23 lie very near in its altitude : Styrax-Weigela-Sasamorpha-Carex sociation in Mt. Neko lacks in the floral element of group 1,plant of Pinion densiflorae ; but Pinus-Stewartia-Symplocos-Rhododendron sociation in Mt. Kuzyu contains some of them, although, extremely surpressed by the group 5. Between the plots 8 and 9,the margin of the dissected valley of the River Oono and its tributaries is crossed by the line, where the grassland flora are replaced by those of the broad-leaved evergreen forests, and the aspect becomes dominated by the pine forest developed on the escarpment of Aso Lava. The other margin of the valiey of Oono is attained between the plots 4 and 2,where the base rock is passed over from Aso Lava to the effusive rock of Sobo Volcano. The characteristic species of the broad-leaved evergreen forest here disappear together with those of the secondary deciduous forest and are replaced by the plants of the beech forest. Along the AC-base line, the woodland on rocky cliffs and land collapses in Mt. Neko is consisted for the most pa
The purpose of this study is to analyze the nest-building behavior of the mouse from a view point of stochastic process. We used a simple method to measure the nest-building behavior quantitatively. The mouse was put in a small box the bottom of which was covered with many pieces of paper. As the mouse used paper for its nest, blank spaces were gradually formed at the bottom of the box with nest-building activities. Accordingly, if the blank spaces are shown quantitatively, it is easy to know the degree of nest-building activity (n.b.a.) on time scale. In this experiment, the bottom of the box was partitioned into 104 parts at right angles and covered with 300 pieces of paper of uniform thickness. By the above-mentioned method, the n.b.a. was measured at intervals of 15 minutes at mean room temperature, 17.2℃, 18.0℃, and 19.4℃ respectively. Further, a stochastic method was made to analyze this n.b.a. process. The estimated mean, N^^^-(t), and estimated variance, Var (N(t)), of cumulative n.b.a. can be computed from equations (7 )and (8) on each trial. In equations(7)and(8), λ and μ are positive and negative intrinsic nesting rates respectively. Therefore, λ-μis, the true intrinsic nesting rate, which is symbolized with ρ and can be calculated from equation(10)or(11). The results obtained from the experiment on 45 mice, 20 of which are males, are given in Table 1,and ρ values in Table 2. The findings in this experiment are that the n.b.a. falls according as the room temperature rises from 17.2℃ to 19.4℃ and that there is no difference in the n.b.a. between both sexes. These results seem to be appropriate to the notions which were already demonstrated by KINDER and others, that nest-building behavior serves as heat-conserving activity. Subsequently, another experiment was conducted to know the effect of previous experiences on the n.b.a.. Thirty-four infant mice were divided into three groups, and given the following treatments. The first group was given neither nest material nor mother mouse and the second group only nest material and the third group both nest material and mother mouse. After about six week's treatment, the n.b.a. was measured. N(t) and N^^^-(t)in this experiment are given in Table 3 and ρ values in Table 4. The first group excelled the others in the n.b.a. as the data show. Therefore it is suggested that, when an instinctive behavior such as nest-building is emitted for the first time from birth by some stimulus, it might become particularly active. Lastly, the goodness-of-fit between the computed n.b.a., N^^^-(t), and the observed n.b.a., N(t), was determined by computing X^2. The values obtained are given in Table 5. It seems that this stochastic model is practically useful for analyzing the nest-building behavior, though there is a significant difference during the first nine trials.
The intertidal zonation of marine algae along the coasts of Sagami Bay was studied. The field work which forms the basis of this paper was commenced in March, 1957 and continued to March, 1958. As the results of the investigations, all the marine algal communities found along the coasts proved to be the open-sea type. No inland-sea community, e.g. Monostroma nitidum-Scytosiphon lomentarius community of Ulva pertusa-Grate. loupia filicina community, were found. The open-sea communities are divided into Gloiopeltis furcata-Myelophycus caespitosus-Hizikia fusifor-me-Eisenia bicyclis community which are found on the eastern part of the bay (Enoshima, Hayama, Aburatsubo), and the Gigartina intermedia-Sargassum sagamianum community on the western part (Oiso, Manazuru, Izusan, Ito, Yatano, Kitagawa). In the former community there can be recognized four belts which are named after the dominant species occurring there. They are, from above downwards, Gloiopeltis furcata belt, Myelophycus caespitosus belt, izikia fusiforme belt and Eisenia bicyclis belt. In the first belt, Gloiopeltis furcata and Gloiopeltis complanata are found. The dominant alga of the second belt is Myelophycus caespitosus and it is associated with the following forms : Ishige Okamurai I. foliacea, Petrospongium rugosum, Porphyra suborbiculata, Endarachne binghamiae and Caulacanthus okamurai. The dominant alga of the third belt is Hizikia fusiforme and it is associated with the following forms : Chondrus ocellatus f. typicus, Gigartina intermedia, Colpomenia sinuosa and Laurencia sp. The dominant alga of the last belt is Eisenia bicyclis and it is associated with the following forms : Sargassum hemiphyllum, S. Ringgoldianum, S : nigrifolium, S. Thunbergii, S. patens and S. sagamianum. The community is distributed over Onahama, Boso Pen., Izu Pen., Ise Bay, Shima Pen. and Hyuganada etc., and it is the characteristics of the Pacific coasts. In the latter community there can be recognized two belts. They are, from above downwards, Gigartina intermedia belt and Sargassum sagamianum belt. The dominant alga of the first belt is Gigartina intermedia and it is associated with the following forms : Gloiopeltis furcata, Gelidium divaricatum, Chondrus ocellatus f. typicus. C. ocellatus f. canariculatus. Carpopeltis flabellata, Nemalion pulvinatum, Grateloupia livida, Myelophycus caespitosus and Ishige Okamurai. The dominant alga of the second belt is Sargassum sagamianum and it is associated with the following forms : Sargassum nigrifolium, Lomentaria catenata, Corallina pilulifera and Grateloupia elliptica. In the community, some of the marine algae are discolored whitish. This community is also distributed over the Kiisuido and Tosa Bay, which is of a special feature. The return current of the sea, the inflow of rivers and the shape of the bay have significance with the distribution of the community.