The adults do not emerge simultaneously even if they develope from a single batch of eggs deposited at the same time and the sequential frequency of their emergence is like the normal curve, but unsymmetrical. NISIKAWA (1939) found that this curve agrees well with the normal distribution when the reciprocal transformation is made in time scale. This has been considered as a good statistical model of the emergence curve. When the azuki bean weevil, Callosobruchus chinensis was reared under three different conditions of atmospheric moisture, the resulted emergence curves were not so different from each other, excepting the regular change in the standard deviation. The curves obtained agree well with the statistical model (Figs. 1 and 2). When the rearing density of the weevil was changed, the shape of the emergence curve changes. With advancing density the skewed part of the right hand portion of the curve disappears and it approaches to a normal curve, and the standard deviation of the average time of development becomes small (Figs. 3 and 4). These changes in the shape of the curve may be caused by differential mortality. The former case is due to the density independent mortality, which distributes randomly at all of the phases on the emergence curve, but in the latter case the mortality concentrates in the hind part of the emergence process.

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This series of experiments was carried out with respect to 38 leading varieties of sesame as material, which were collecte in eight countries including Japan, to find the change in germination conditions, varietial differences, and the relation to several of their characters, seeding them at the depths of 0.5,1.5,3,5 and 7 cm each. The results of the experiments are as follows : 1) The deepest limit of seeding which permitted germination was 5 cm. African varieties attained the best germination both in shallow and deep seeding. 2) Israel varieties produced no better results than the other varieties in shallow seeding, but they showed germination next best to the African varieties, in deep seeding. 3) Generally, the African varieties required the least average number of days for germination, with American and Korean varieties following. 4) The covariance of the welght of the 1000 seeds and germination coefficient in 0.5 cm seeding, from the view point of all varieties, had (-) correlation, and the heavier the seeds the lower germination coefficient they showed, and within groups they also showed the same (-) correlation. On the other hand in deep seeding (-) correlation was seen concerning all varieties and also with groups. The heavier the seeds the higher the germination coefficient. 5) The covariance of the days from seeding to flowering and the germination coefficient, there was no correlation whatever in (0.5 cm) shallow seeding. But in deep seeding (5 cm) such late varieties as African and Indonesian showed higher germination coefficients, while such early varieties as Korean and such medium varieties as American showed lower germination coefficients. 6) The covariance of the oil contents and the germination coefficient : the more oil the seeds contained the worse germination followed in shallow seeding ; while in deep seeding comparatively better results were recognized. 7) When germination in the germinater was compared with that in the field, the germinater and the field gave the same results in shallow seeding. In the case of the Israel and Indonesian varieties, those varieties that showed the higher germination coefficient in the field showed the lower germination coefficient in germinater. The varieties that showed the higher germination coefficient when sown at the depth of 5cm showed the lower germination coefficient in the germinater. African and Chinese varieties showed the same germination tendency either in the germinater or in the field.

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The intertidal zonation of marine algae along the coasts of Toyama Bay, facing the Japan Sea, was studied. The field work was carried out in spring, 1958. Enteromorpha compressa-Scytosiphon lomentarius community is remarkable in the bay (Table 1). In this community there can be recognized two belts which are named after the dominant species. They are, from above downwards, Enteromorpha compressa belt and Scytosiphon lomentarius belt. The dominant alga of the former is Enteromorpha compressa and associated with this are the following forms : Cladophora utriculosa, Porphyra Okamurai and Bangia fuscopurpurea. The dominant alga of the latter is Scytosiphon lomentarius and associated with this are the following forms : Gymnogongrus flabelliformis, Gigartina intermedia, Enteromorpha linza, Corallina pilulifera, Chondria crassicaulis, Ulva pertusa, Grateloupia divaricata and Sargassum thunbergii. This community shows a distinctive characteristic of the inland sea. But in the eastern part of the day, it shows some characteristics of the open sea. And in the western part, the marine algae are discolored whitish. The return current of the sea and the inflow of rivers are most significant for those facts. The vertical width of the community is apparently much narrower. This is the special feature of the Japan Sea. An important point in reference to this phenomenon is the tidal factor.

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The annual succession extending from 1950 to 1958 of Desmids communities in Tatara-numa, a small lake, has been studied with attention to the organic pollution. As shown in Fig. 1,Tables 1 and 2,the Desmids communities have succeeded during these years as follows : Desmidium-Micra-sterias period→Cosmarium period→Staurastrum-Cosmarium period→Cosmarium period. When the lake was subjected to the highest degree of pollution in 1955-1956,the Desmids communities almost disappeared, especially the species of the genus Micrasterias and also those of large types of other genera entirely vanished. On the other hand the species of Scenedesmus, and those of smaller types of Cosmarium and Staurastrum occurred remarkably.

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Innerhalb der warm-temperierten Region der ganzen Erde sind die Lorbeerwalder im feuchten Klima vorherrschend, im trocknen Klima aber die Hartlaubwalder oder-gebusche. In Nordhemisphare ist das beste Exemplar zu den ersteren der Shiia-Wald von Japan (Shiion Sieboldi) und zu den letzteren der Quercus ilex-wald des Mittelmeergebietes. Die Hartlaubgebusche von Eichenarten der Sektion Ilex sind aber manchmal innerhalb des Klimaxgebietes des Waldassoziation von Shiia-typus Lokalisiert zu finden. Das ist bei Quercus phylliraeoides in Sudwestjapan der Fall. Tanoura (Probebestand A-Shiia-Wald) und Youra (Probestand B-Quercus phylliraeoides-Maquis und-Garigue) liegen in der sudwestlichen Ecke von Setouti, dem japanischen Mittelmeer. Vom makroklimatischen Standpunkt aus, vermindert sich die Sommertrockenheit von A zu B (Abb. 1), d. h. der Mittelmeerklimacharakter verschwindet allmahlich. Um die Lebensrhythmus feldmaBig zu erfassen, bestimmten wir die osmotischen Werten von Dominant-und Charakterarten durch die kryoskopischen Methode. Das Jahresmaximum des osmotischen Wertes liegt bei Quercus phylliraeoides um etwa 8 Atm hoher als bei Shiia. Dies ist eim Organisations-merkmal, unabhangig vom Makroklima. Es ist naturlich, daβ die kurve des osmotischen Wertes von Krautschichtpflanzen milder als die von Waldbaumen verlauft. Wahrend der Kaltenperiode steigt die Kurve von Waldbodenfarnen (Dryopteris erythrosora) hoch und schreitet die von Waldbaum (Shiia) im Berg Rokko (an der Nordostkuste von Setouti) uber. Aber in Tonoura erreichen die Maximumpunkte von Farnpflanze (Rumohra) und Halbstrauch (Ardisia) nicht die Hohe des osmotischen Wertes von Shiiabaum. Unter dem Kronendach der Quercus phylliraeoides-Marquis oder-Garigne konnen stenohydrische Farnen nicht mehr bestehen, und an deren Stelle wachst auf dem Felsboden eine polikilohydrische Farne, Cyclophorus lingna, die sonst in den subtropischen Regenwaldern ein Epiphyt ist. Machilus ist zwar eine wichtige Domiantart des Lorbeerwaldes, aber keine Pressaft ist davon zu gewinnen, weil sein gekochtes Laub sehr klebrig wird.

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The analyses of the behavior reactions to the vibrating stimuli have been attempted only on some aquatic insects and terrestrial spiders. There have been some reports of direct reactions (taxes) to the vibrating stimuli, for example, by EGGERS (1926,1927) on Gyrinus ; by SHIMA (1940,1942) and by HONJO (1945) on Dineutus ; afterwards by BAERENDS (1950) on Notonecta. On the other hand, MORI (1938,1950) recorded the tidal rhythmic activity of a small bivalve, Donax semignosus, a sandy-beach inhabitant with a rhythmic behavior evoked with the stimuli of mechanical vibrations caused by waves. No direct reaction to the vibrating stimuli, however, has been investigated on a small terrestrial crustacean. It is no doubt due to the difficulties of controlling and measuring the conditions and evolving technique as accurate and precise as that can be used when mechanical vibration is the stimulus. The author has shown that the shore sowbug, Tylos granulatus, takes a characteristic behavior under natural conditions, to and from the water edges, accompanied with the periodic movement of waves in the night (ONDO, 1958). The present work is attempted to analyse the mechanisms in a behavior qualitatively, in terms of elementary animal behavior. Experimental analyses were carried out in the laboratory, using fresh and reared materials from 1954 to 1956. The material, apparatus and methods to relaese the direct reactions to the vibrating stimuli used in the study have been discribed in the previous paper (ONDO, 1958). Some results obtained will be stated in this paper. 1. Animals exhibit a turning locomotion avoiding the stimuli when the substratum of vibrating plate was vibrated and an approaching to the region of low intensity. In such behaviors, it is confirmed by means of the two-stimuli-source experiment and the unilateral removal of receptors, that negative tropo-taxis does occur, i.e., being removed the left (right) antenna, animals move round in general leftwards (rightwards) just like a circus movement. 2. When seven distal segments of both the second antennae were removed, animals still were able to response to the stimuli of mechanical vibration caused by electric tuning fork, but if the second basal segments of both antennae were removed, the sense of vibrating stimuli was lost. These results may only be understood, when it is assumed that the receptor of vibrating stimuli is located on the second basal segments of both antennae. 3. Periodic behavior accompanied with the periodic movement of waves is based upon the sense of the mechanical vibrating stimuli, therefore, such a periodic behavior exhibited by the shore sowbug has an endogenous feature in its nature. 4. The present writer is in the opinion that the periodic behavior accompanied with periodic movement of waves exhibited by the shore sowbug, may be one of the physiological adaptations in individual level to the inorganic waves, from thee. g., periodic movement of environmental elements, ecological viewpoint.

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