On the variation of leaf characters of an Antarctic moss, Bryum inconnexum

The taxonomical status of Bryum inconnexum CARD., one of the most common mosses found on ice-free areas in and around Ongul Islands, is still inconclusive. One of the reasons bringing about such condition is a good deal of variability in their morphological characters. This study is made to understand precisely the actual state of the variation of the leaf size and the leaf shape. An individual plant of this moss grows taking the innovation system of monopodial sympodium. The leaves of an innovation shoot show a remarkable variability in the size and the shape as well as in the length and stoutness of the midrib according to their position in an innovation. The correlation between the variation of leaf characters and the water condition in their habitat was analyzed using the specimens from the sandy bank of a brook where the water condition changed gradually from the center of stream to the upper part of bank. Generally, the leaf size is smaller and more diversified in the dry habitats than in the moist habitats. On the other hand, the leaf shape seems to be invariable independently of the water condition in their habitat