ABSTRACT

Marattiaceae is a small family whose generally large plants still resemble their ancient fossil relatives closely. The striking feature of the family is the sorus which is composed of a group of sporangia in which several layers of laminar cells are fused together to form a synangium or a pseudo-synangium. By this feature the family Marattiaceae differs from ‘modem’ fems which produce sporangia from a single layer of cells. The Marattiaceae are eusporangiate fems rather than true modem leptosporangiate fems.Plants of the family are terrestrial. The rhizome is erect or has the form of a small stem., a polycyclic dictyostele. Pinnate fronds, small to huge, are attached to the rhizome (i.e. the stem) and are flanked at their base by two hard, hand­ sized auricular stipules. Spores escape through a slit at one side or by an apical pore from the capsule-like synangium. Of the six genera only two are found in Sri Lanka.