| Abstract: | The development of the sporophyte-gametophyte interface in themoss, Funaria hygrometrica Hedw., is described with the aidof light- and electron-microscopy. The outer walls of the cellsthat abut the haustorial cavity in both generations developlabyrinths typical of transfer cells. This feature is more apparentin the epidermal cells of the sporophyte foot (haustorium),where development can be split into three main stages. The primarygrowth stage, which is complete at about the time the calyptradetaches from the ripened archegonium, involves the formationof transfer cells. The secondary stage is characterized by thedeposition of amorphous inclusions in the wall labyrinth ofthe transfer cells. The tertiary stage, which commences as thesporophyte capsule ripens, entails de-differentiation of thetransfer cell wall labyrinth to form a thick, heavily encrusted,outer cell wall. The pattern of development of these cells iscorrelated with changes in gametophyte- sporophyte translocationcapabilities. |
