シワヤハズ及びジガミグサ(褐藻,アミジグサ科)に於ける栄養繁殖

Results of the present writer's observations on vegetative propagation occurred in Dictyopteris undulata Holmes and Stypopodium zonale (Lamouroux) Papenfuss (Dictyotaceae, Phaeophyta) in nature are presented in this report.
Vegetative propagation in Dictyopteris undulata occurred solely from the midrib of the blade. Gemmae were conical to subcylindrical or compressed and underwent apical growth at early stage of development. Thereafter they became broader and flattened by replacing an apical cell to the marginal meristem, and gemmae developed into the typical foliose blade with a midrib.
In Stypopodium zonale vegetative propagation occurred solely from the primary rhizoids. Gemmae were cylindrical to subcylindrical or compressed and underwent apical growth at early stage of the development. Thereafter gemmae became broader and flattened by replacing an apical cell to the marginal meristem. Then they developed into typical fan-shaped blades.