Percurrent proliferations in fungi, algae, and mosses

Abstract

The production of new reproductive structures at the apex of successive percurrent proliferations is a common phenomenon in fungi. Successive sporangia and conidia in Phycomycetes, successive asci, conidia, phialides, and possibly 'gemmae' in Ascomycetes, and successive probasidia, basidia, and apparently urediniospores in Basidiomycetes, can be produced in this way. Examples of these are given from published accounts and some personal observations. Successive reproductive structures of various kinds are also formed on percurrent proliferations in 'green,' brown, and red algae. In the red algae successive antheridia can develop within empty ones by this method; it is concluded that such antheridia are not phialides. Successive gemmae in some mosses are formed terminally on percurrent proliferations.