STRUCTURE OF THE SPOROPHYTE GAMETOPHYTE JUNCTION IN TMESIPTERIS-ELONGATA PA DANGEARD (PSILOTACEAE, PSILOTOPSIDA) AND ITS PHYLOGENETIC IMPLICATIONS - A SEM ANALYSIS

SEM-analysis of the sporophyte-gametophyte junction in Tmesipteris elo ngata P.A. Dangeard (Psilotaceae, Psilotopsida) revealed a well-define d bulbous haustorial foot with a conducting strand, targe parenchymato us cells in the central region of the foot, and haustorial cells resem bling those in the Anthocerotae. In the placental region, sporophytic haustorial cells are closely intermingled with gametophytic transfer c ells. The interior side of the walls of transfer cells is tuberculate with numerous 'wall-ingrowths' of about 1 mu m length. There are inter cellular spaces between the two cell types. This finding may support a closer relationship between Psilotopsida and Anthocerotae.