Abstract
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.
