The morphological and anatomical analyses of leaves in the serpentine ecotype of Adenophora triphylla var. japonica (Regel) H. Hara were carried out. In comparison to the normal type of this variety, the serpentine ecotype has a narrower leaf due to decrease in the number and size of cells. The stenophyllization process of the serpentine ecotype is similar to that of the rheophytic ecotype. The study further indicates that the decreased number and size of cells is a general tendency in stenophyllization. By contrast, leaf thickness and stomatal density of the serpentine ecotype differed significantly from those of the rheophytic ecotype, suggesting that the two ecotypes are differently adapted to solar radiation and evaporation.

The morphology and anatomy of leaves of rheophytic and non-rheophytic types of Adenophora triphylla (Thunb.) ADC var. japonica (Regel) H. Hara were compared in order to clarify how leaf characteristics differ. Our results revealed that the leaf of the rheophytic type of A. triphylla var. japonica was narrower than the leaf of the non-rheophytic type because of fewer cells that were also smaller. Moreover, surprisingly, the rheophytic ecotype of A. triphylla var. japonica was thinner than that of the non-rheophytic type, although the general tendency is that the rheophytic leaf is thicker than the closely related non-rheophytic species, suggesting that the rheophytic type of A. triphylla var. japonica adapts differently, as compared to other rheophytic plants, to solar radiation and evaporation.

The comparative morphology and anatomy of leaves between the coastal ecotype and the normal type of Adenophora triphylla (Thunb.) A.DC. var. japonica (Regel) H.Hara (Campanulaceae) were examined to clarify the differences in morphological characters between the 2 groups. Morphological and anatomical analyses revealed that the coastal ecotype had a thicker leaf than the normal type, because of the increased size of epidermal and spongy cells. Thus, the main morphological change from the normal type into the coastal ecotype of A. triphylla var. japonica is the increase in leaf size, suggesting that the coastal ecotype may have evolved from the normal type via a heterochronic process.

The distribution of Aster hispidus Thunb. var. insularis (Makino) Okuyama is limited to the coastal areas of southwestern Shikoku. This species has been described as having fatter stems, thicker leaves, and glabrous stems and leaves ciliate on margin. We have found many individuals that ranged from having no hair to many hairs on the abaxial side of the leaves in this variety. We measured the number of leaf hairs, degree of herbivory, and stomatal density of leaves of A. hispidus var. insularis. Two types of A. hispidus var. insularis for the presence or absence of leaf hairs were obsereved. The degree of herbivory did not differ significantly between these two types, however, the stomatal density was lower in the hairy-leaf-type individuals than in the hairless-leaf-type individuals.

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