[in Japanese]

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Mt. Asama situated in the northern part of the Shima peninsula and attains a height of 553m. Mostly serpentine rocks underlie this mountain. The field work which forms the basis of this paper was carried out between September and November, 1956. The serpentine area of this mountain is infertile, and the dwarfish communities cover most of those parts. As the dwarfish communities, Pinus Thunbergii-Pourthiaea leavis and Pinus densiflora-Pourthiaea laevis communities are remarkable, and the composition is variable according to soil depth, serpentine exposure and drying. The first community is found on the parts where serpentine exposure is severe and driness sharp. In the community, it's destitute of the 1st layer. The 2nd layer is consisted of scattered, dwarf Pinus Thunbergii of about 2.5 m. in height. The 3rd layer is dominated by Pourthiaea leavis of 1.5 m. in height, and among the plants Fraxinus Sieboldiana var. serrata, Stephanandra incisa, Diplomorpha Ganpi, Abelia spathulate and Berberis Thunbergii var. Maximowiczii are found. In the 4th layers, there are Miscanthus sinensis, Pertya scandens, Rosa Wichuraiana, Smilax China and Salvia isensis. The second community is found on the parts where shallow soils, 20 cm. deep, cover over the underlying serpentine. In the community, it's also destitute of the 1st layer. The 2nd layer is consisted of scattered, dwarf pinus densiflora of 3 to 4 m. high. In the 3rd layer, Pourthiaea leavis is abundant and fraxinus Sieboldiana var. serrata, Abelia spathulata, Stephanandra incisa, Lespedeza Buergeri, viburnum erosum var. punctatum, Rhododendron reticulatum and Millettia japonica mixed. The 4th layer is composed of Miscanthus sinensis, pertya scandens, Rosa Wichuraiana, Smilax China, Diplomorpha Ganpi, Salvia isensis, Chrysanthemum Makinoi, Juniperus rigida, Thalictrum Thunbergii var. hypolencum and Berchemia racemosa.

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