P. megiston Schult. Stout, erect perennial, l-2 m tall; culms glabrous. Sheaths shorter than the internodes, sparsely papillose-pilose; ligules irregular and ciliate at apex, lacking long trichomes behind the ligule; blades 15-40 cm long, 15-30 mm wide, glabrous but with scabrid margins. Inflorescence a terminal panicle 40-60 cm long, the main axis +/- stout, the branches slender, whorled at intervals; spikelets obovate to subglobose, pedicellate, 2.7-3.3 mm long, glabrous; first glume about one-fourth as long as spikelet; second glume and sterile lemma covering fruit. Fruits greenish-white, ca 3 mm. long, smooth, obovate. Croat 11804. Infrequent, but locally abundant in quiet marshes. Flowers and fruits in the rainy season, mostly in the early rainy season.