prothallium

== English == === Etymology === From Latin pro (“forwards”) + Ancient Greek θᾰλλός (thăllós, “young branch, twig”). === Noun === prothallium (plural prothallia) A plant, usually a pteridophyte, in gametophyte stage in the metagenesis cycle. The young gametophyte of a liverwort or peat moss. ==== Synonyms ==== prothallus