Phylogeny and Affinities of Acromastigum

Abstract

The classification adopted in this revision proceeds in a general way from simpler and less highly differentiated to more complex and more highly differentiated forms. In A. bancanum, for example, which comes near the beginning of the series, the leaves and under-leaves are composed of a relatively small number of cells and are undivided. In A. inaequilaterum, on the other hand, which comes near the end of the series, the leaves and underleaves are composed of a relatively large number of cells, the leaves are definitely bifid, and the underleaves definitely trifid. A higher differentiation is further expressed by the marginal teeth of the leaves and underleaves and by the frequent occurrence of cuticular tubercles.