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.