The anomuran crab, Lithodes aequis pina BENEDICT, is a species allied to the famous northern king crab, Paralithodes camtschatica (TILESIUS). In spite of the high commercial value of Lithodes aequis pina, the species has been confused with other Paralithodes and Lithodes species in the catch statistics. 1) A biological and fisheries survey on Lithodes aequispina was conducted by the Fisheries Experiment Station of Chiba Prefecture on the ocean floor from 400 to 900 meters depth off Boso Peninsula, Chiba (Fig. 2), and in Sagami Bay (Fig. 3) from November 1968 to March 1970. 2) By setting 11,045 crab pots (Fig. 1) during 104 operations, a catch rate of 0.345 crabs per pot was obtained. There was no great difference in localities except for a very poor catch in Sagami Bay, but there was an irregular seasonal variation in catch per pot, generally decreasing from summer to winter (Fig. 4). The results suggest that the fishing efforts will not be compensated by the market value at this stage. 3) Carapace width range from 8.3 to 19.2cm in the females and from 8.0 to 22.0cm in the males (Fig. 5). The maximum size of the adult crabs was 22.0cm in the males and 19.2cm in the females in this observation. 4) The minimum size of the females incubating eggs on their appendages was 10.5cm in carapace width (Fig. 6). Fifteen per cent of females of 12.6cm in carapace width carried eggs and 60per cent of the females of 13.6cm in carapace width carried eggs. In this paper the females larger than 13.6cm in carapace width are treated as adults. 5) It is assumed that the spawning period continued from July to October ; the incubating period continued from October to February in the following year ; and the hatching period continued from February to July (Fig. 7). The sex ratio in the fishing grounds altogether (400-900 meters depth) was nearly 1 : 1 in the spawning season, while the ratio of the females increased in incubating and hatching periods (Fig. 8). 6) The ratio of the adults to immature (adults/immature) forms was about 3 : 4 from June to September and about 7 : 3 from October to December. At a depth of 400-600 meters the ratio between the adults and immatures was high, while at a depth of more than 600 meters it was low (Fig. 9). 7) The number of incubating eggs at the new egg stage was correlated with the carapace width of the crab at the coefficient of correlation, 0.648. The number of eggs ranged from 9,500 to 30,100 per individual female from 12.9cm to 15.7cm in carapace width (Fig. 10).

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There are two main objects in the present study ; the first is to investigate the seasonal variation of litter fall, and the second is to measure the rate of litter decomposition, relating to the environmental factors of the stands studied. For estimating the amount of litter fall, a quadrat of 20×20m in size was set in each stand and nine circular traps with a wire frame covered with nylon net (0.6m in diameter and 0.7m in height) were established, using the method of MIYATA and OMURA (1967). The seasonal variation of litter fall was studied in relation to the developmental progress of some ever-green coniferous forests at the Ebino Heights, in the southern part of Kyushu. The litter fall was concentrated in autumn in all stands, and showed a synchronized seascnal variation irrespective of the difference in age and floristic composition of the stands. To determine the rate of decomposition, the litter bag method was applied. The sample leaves were laid evenly in the bag of 16×16cm in size, which is made of polyethylene net. The analysis of the relationships between the decomposition rate of litter and two main environmental factors (air-temperature and precipitation) was carried out. As the results of this analysis and making reference to the calculation of MADGE's data, the author proposed the following two equations. [numerical formula] [numerical formula] where N and No are the amounts of organic matter at the time t and the initial stage, respectively and a, a', b, b' show the constants. Equation (1) is applied to the area where precipitation is sufficient and air-temperature is low, as in the case of the Ebino Heights. Equation (2) is applied to the area where air-temperature is high and precipitation is insufficient, as in the case of Ib■dsn, Nigeria.

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Various experiments were conducted with the seeds of Erythrina variegata to study the imbibition and germination behaviour. The characteristics of seeds with reference to weight, volume and dimensions per seed have been studied. It has been observed that imbibition and germination in ordinary laboratory conditions of light and temperature were 100 and 80 percent respectively in a control set. Tne temperature treatment at 35℃ proved beneficial to 95 percent germination. Higher temperature treatment to seeds proved to be harmful. Acid pre-treatment to seeds and exposed to light quality viz., red, yellow, green and blue, have enhanced the imbibition and germination to 100 percent within 6 days. Forty minutes acid pretreatment to seeds in blue light has helped to complete 100 percent germination in 3 days. Pre-treatment of seeds to chemicals such as (i) Ammonium chloride (ii) Potassium nitrate (iii) Ammonium nitrate and (iv) Absolute alcohol was given in hours. Ninty to 100 percent germination was observed in (i) ammonium chloride -10 hours, (ii) potassium nitrate -1 hour, (iii) ammonium nitrate -2 hours and (iv) 2,4 and 24 hours in absolute alcohol. Culture experiment in different soil types was also performed and 90 to 100 percent germination was obtained in gravel and sandy soils respectively. The root/shoot ratio in length and oven dry weight was also studied.

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Der erste Verfasser hat die Vegetation der Kuzyu-Vulkangruppe pflanzen-soziologisch untersucht. Das Maianthemo-Rhododendretum und sein Subassoziation vaccinietosum wurden dadurch wieder festgestellt. Am Gipfelteil vom Hossyo-, Inabosi- und Kuroiwa-Berg kommt Juniperus chinensis L. var. sargentii HENRY in der Assoziation vor. Die Vergesellschaftung von Rhododendron und Vsccinium mit Juniperus ist sehr interessant, denn diese Gattung dominiert in alpinen Stufen von Formosa an Stelle von Pinus pumila REGEL in alpinen Stufen Japans. Ubrigens ist eine von Polygonum bistorta L. dominierte Hochstaudengesellschaft an der Leeseite des Wintermonsuns neulich gefunden. An den vermoorten Standorten wurde eine neue Subassoziation vom Cirsie-Molinietum festgestellt. Die zweite Verfasserin hat die vom ersten Verfasser gesammelten Bodenproben untersucht. Ein podsoliertes Profil wurde mindestens morphologisch nie aufgefunden. Die pH-Werte von einigen A-Horizonten waren ungewohnlich niedrig [pH (H_2O) gewohnlich 4.0-4.5,im extremen Falle 2.5]. Die Ursache davon ist wahrscheinlich dem Schwefeldampf von den Sulfataren zuzuschreiben.

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The area studied is situated at an altitude of about 300 m near the Narugo spa in the northwestern part of Miyagi Prefecture. In the central part of the area there is a small lake, Katanuma ; this was a crater of the ancient Nargo volcano. Though the volcano is not active, gas containing hydrogen sulfide and sulfurous oxide, etc. has been issuing through many small holes on the bottom and shore of tne lake for more than 20 years. And, a solfatara field was established. A small factory refining the sulfur from the sulfur deposit at the bottom of the lake, was constructed on the northern shore of the lake about 30 years ago. The vegetation of the area has been wasted by such harmful gases as hydrogen sulfide and sulfurous oxide. Subsequently the greater part of the area become covered by characteristic plant communities. Based on the physiognomy and floristic composition the vegetation of the area can be distinguished into eight plant communities as follows ; Carex angustisquama community, Miscanthus sinensis community, Miscanthus sinensis-Cladonia crassensis subsp. japonica community, Sasa palmata community, Sasa palmata-Miscanthus sinensis community, Vaccinium ovalifolium-Vaccinium hirtum community the secondary forest of Quercus serrata and the planted forest of Pinus densiflora. With the decreasing of the harmful action of the gases, the vegetation changed and can arranged in the following order : the bare ground-the Carex angustisquama community-Miscanthus sinensis-Cladonia crassensis subsp. japonica community-Vaccinium ovalifotium-Vaccinium hirtum community or Sasa palmata community. By the intense weathering has of the original solfatara soil, the crystaline minerals were destroyed and aluminum, iron and other cations washed away, resulitng in a white silica-rich material. Mineralogical study showed the existence of volcanic ash soil at some places. With the increasing of the distance from the solfatara, the extent of the mixing of volcanic ash soil increases. A clear relationship can be recognized between the soil and the vegetation. Successions of the soils in the solfatara field is influenced by both the mixing of volcanic ash soil and the plant succession.

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Recent ecological surveys and some items of IBP research require the direct recording of the environmental signals and gaseous exchange of plants in their natural stand. To meet such requirement, two commercial vans were refitted as a moving laboratory. One of the vans was provided with an assembly involving the measurement and recordings of CO_2 concentrations from six different sources of air and 48 different environmental factors such as solar radiation, wind velocity, dry and wet bulb temperatures, CO_2 concentration, etc. within six minutes, and also a generator with electric power capacity of 3 kw. Another van was made to provide an extra 5 kw electric power to drive a cooling unit and a one-HP blower to blow air into an assimilation chamber of 70×70 cm^2 in basal area with varying height up to 225cm and to illuminate leaves for photosynthesis measurement.

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