Studies on the sporeling of Japanese mosses (3) Eccremidium minutum (Mitt.) Stone et Scott and Pseudephemerum nitidum (Hedw.) Reim.

Abstract

  Germination of fresh spores and development of sporelings were studied in three species of mosses which are possible recent introductions to Japan. Sporelings of both Eccremidium minutum and Pseudephemerum nitidum belong to the Bryum-type. Iwatsuki and Takaki (1979) reported that spores of E. minutum were large (65-150 μm) and most of them were aborted. In the present study these aborted spores did not germinate, and we observed only a few germinated spores. Almost all spores of P. nitidum germinated easily. Young leafy gametophytes of this species were produced on the caulonemata. Leafy gametophytes grew very fast compared with those of perennial mosses. Spores of Ephemerum spinulosum did not germinate, although we tried four times in 1979 and 1980.