[in Japanese]

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Karyotypes are studied in eight species and two subspecies of Japanese Saussurea. All of the species examined have 26-chromosomes in diploid condition, but two of them have B-chromosomes which vary between 2 and 12 in number. The largest chromosome is about 5 μ in length and the smallest about 2 μ. The thirteen pairs of chromosomes at mitosis in the root tip are usually observed in all the species investigated. The large and the small four pairs of chromosomes can be easily distinguished from the other nine pairs of chromosomes which vary gradually in size. The first pair has median centromere and the second pair submedian, while the thirteenth pair has terminal centromere. Difference of the karyotypes in each species is observed in the other ten pairs of chromosomes. S. amabilis has four pairs of median chromosomes, while S. gracilis and S. ussuriensis have three pairs of submedian chromosomes. S. triptera has five pairs of subterminal chromosomes, while S. nipponica subsp. sendaica has six pairs of terminal chromosomes. Considering the karyotypes of these species examined, S. amabilis is different from the other species. Similarity of the karyotypes is found in both S. gracilis and S. ussuriensis, and in both S. sinuatides and S. nipponica subsp. savatieri, respectively. On the other hand, difference of them is observed in the subspecies of S. nipponica : subsp. sendica and savatieri.

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Ranzania japonica is observed in its floral anatomy with special reference to the floral vasculature. Several interesting morphological features are observed: 1) In the receptacle the central bundles are surrounded by the several cortical bundles. 2) The central bundles give off a trace bundle to each of outermost three sepal, one or two rarely three trace bundles to each of petaloid sepals, and usually two trace bundles to each of petals and stamens. 3) To the petaloid sepals and the petals the cortical bundles separate trace bundles which enter these organs as laterals. 4) The vascular network is scarcely observed in the receptacle, for the central bundles usually do not fuse together. 5) In each pistil, two ventral bundles and one dorsal bundle are observed in typical forms, though there are a few pistils with only one ventral bundle or no dorsal bundle. 6) The ovules of the lower to middle portion of the locule receive the vascular supplies mainly from the bundles other than the ventral bundles. While, the ovules of the middle to upper portion of the locule receive the vascular supplies mainly from the branches of the ventral bundles. 7) The ovular bundles are formed by successively dichotomous branching or fascicular branching.

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In the course of biosystematic study on Viola vaginata and V. Bissetii, the geographical variations in leaf shape in these species were examined. Viola vaginata is distributed mainly in the Japan sea side of Honshu and Oshima peninsula of Hokkaido and is considered as one of the Japan sea side elements. On the other hand, V. Bissetii occurs in the Pacific side of Honshu, Shikoku and Kyushu. The leaf of V. vaganita exhibited a clinal variation in shape from North to South in its distribution area. Larger and broader leaves were found in northern region, while smaller and narrower leaves in southern region. In contrast, the leaf of V. Bissetii was observed to show discontinuous variation and not a clinal variation in shape. Considering the variations of leaf in shape and texture, two varieties are recognizable in this species : var. Bissetii is distributed mainly in Honshu, and var. kiusiana occurs in Kyushu and western Shikoku.

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