Life-cycle of Porphyra capensis Kütz.

Abstract

ALTHOUGH germination of the spores of Porphyra has been observed under cultural conditions by a number of workers^1,2, the complete life-cycle of this plant, from the germination of the carpospore to the re-establishment of the leafy thallus, has never been conclusively demonstrated. The most recent work has been done with. P. umbilicalis (L.) Kütz. by Drew^1,3, who has shown that the filaments produced by the carpospores of this species will penetrate shell and afterwards form growths which appear to be identical with those of Conchocelis rosea Batters⁴. Sporangia-like bodies (termed ‘fertile cell rows’ by Drew) developed in the cultures; but no spores were formed from these. Evidence of spore formation was obtained, however, from some similar growths occurring naturally in the scales of the barnacle Pollicipes cornucopia Leach⁵.