43. Oropetium, Trin.
A very small densely tufted erect annual. Leaves are filiform. The inflorescence is a simple slender curved spike. Spikelets are very minute, one-flowered, half immersed in the alternating distichous cavities of the rachis of the spike; rachilla is bearded. There are three glumes in the spikelet. The first glume is very minute, empty, hyaline and persistent. The second glume is linear-lanceolate, rigid, empty, persistent recurved when old, tip obtuse or emarginate. The third glume is shorter broader, hyaline, one-nerved, obtuse or truncate, palea is narrow with smooth keel. Lodicules are not found. Stamens are three. Grain is oblong terete and free.
Oropetium Thomæum, Trin.
This is a very small densely tufted annual grass, never exceeding 3 inches in height and with compressed slender, tough stems.
The leaf-sheath is compressed, membranous, short and open. The ligule is an erect lacerate membrane.
The leaf-blade is filiform, shorter or longer than the stem, erect or curved, coriaceous with the margins sparsely ciliate with long strict hairs, 1/2 to 1 inch long.
The spikes are solitary or fascicled curved on very short branches 1 to 1-1/2 inches long; rachis is green, undulating, tetragonous, with a broad central nerve on the flat faces.
