The purpose of this study is to investigate how the gemmae of Hyophila tortula (Schwaegr.) Hampe reproduce. Since the fruiting- stage in Hyophila tortula has not been reported as a common means of reproduction)3) nor has it been seen in all the Taiwan plants examined for this study, its reproduction by means of gemmae must have played an important role in the perpetuation of its species. Previous papers pertaining to the ontogeny of the gemmae of Hyophila tortula include: (1) Cor-rens, C. 1899, Untersuchungen iiber die Vermehrung der Laubmoose durch Brutorgane und Stecklinge and (2) Andrews and Redfearn, 1965, Observations on the Germination of the Gemmae of Hyophila tortula (Schwaegr.) Hampe, Bryologist Vol. 68,3,345-347. The former summarized the production of protonema from the germination of the gemmae of Hyophila tortula, while the latter reported a production of secondary-gemmae, in addition to the production of protonema from gemmae germination of the same plant. Apparently, both papers did not record the development of the leafy gametophyte from their respective cultures. The present investigation, however, based on the results of repeated experiments revealed not only the production of protonemata occurring in the germination of the gemmae of Hyophila tortula but also the development of mature gametophytes arising from the protonemata produced by the gemmae. These experiments have been repeated and each time came out with the same results.