メシダ科の有節毛

抄録

1. The trichomes of the Athyriaceae are observed, and the classification is revised chiefly based upon the features of the articulated hairs, with special reference to Athyriopsis, Dryoathyrium, Lunathyrium, and some others. 2. The articulated hairs of Athyriopsis, Dryoathyrium, and Lunathyrium are interpreted here as the extremely reduced scales and not identical with the other typical hairs, because there are successively transitional forms between those articulated hairs and the scales, and both of them bear the same type of glandular cells at the apex. 3. The genus Lunathyrium is here revised as to include all the species of Athyriopsis, Dryoathyrium, Lunathyrium, and such species as Lunathyrium bonincolum of the Bonin and the Volcano Islands and Athyrium kaalaanum, A. macraei (=A. proliferum), A. mauianum, Diplazium fenzlianum and D. marginale of the Hawaiian Islands. The key characters to this enlarged genus are to be found in the articulated hairs as well as the groove of the upper surface of the leaf axis, the chromosome number, the gametophytic features, and so on. 4. The genus Lunathyrium so defined is better classified into four subgroups or sections: Athyriopsis, Dryoathyrium except for D. henryi, D. pterorachis and their close relatives which are better placed in Lunathyrium, Lunathyrium s.str., and a group consisting of L. bonincolum and several Hawaiian species mentioned above. These subgroups will be defined on the basis of such features as the rhizome, base of stipe, trichome, sorus, and spore. 5. Acystopteris and Monomelangium have been related to Lunathyrium, based mainly on the presence of the articulated hairs. In spite of such an apparent similarity, Acystopteris and Monomelangium are better placed in Cystopteris and Diplazium, respectively.