589 
GRAMINEjE. (grass family.) 
from Rhode Island southward along the coast. Aug. — Makes a di¬ 
rect transition to the next genus. 
21.TRICUSPIS, Beauv. (Uralepis & Windsoria, Nutt,) 
Spikelets 3 - 12-fiowered, somewhat terete; the terminal flower 
abortive. Glumes unequal. Rachis of the spikelet bearded below 
each flower. Paleae membranaceous or rather chartaceous; the 
lower much larger than the 2-toothed upper one, convex, 2-3- 
toothed or cleft at the apex, conspicuously hairy-bearded or villous 
on the 3 strong nerves, of which the lateral are marginal or nearly 
so and usually excurrent, as is the mid-nerve especially, into a 
short cusp or awn. Stamens 3. Stigmas dark purple, plumose. 
Grain oblong, mostly gibbous.—Leaves taper-pointed: sheaths 
bearded at the throat. Panicle simple or compound ; the spike- 
lets often racemose, purplish. (Name from the Latin tricuspis , 
three-pointed, alluding to the lower palea.) 
§1. Tricuspis proper. (Windsoria, Nutt.) — Glumes shorter than the 
crowded, Jlowers: loicer palea 3 -cuspidate by the projection of the 
nerves , and usually with 2 intermediate membranaceous teeth; the 
upper one naked. 
1- T. scslerioides, Torr. (Tall Red-top.) Culm upright 
(3P-5° high), very smooth, as are the flat leaves; panicle large and 
compound, the rigid capillary branches spreading, naked below; 
spikelets very numerous, 5-7-flowered, shining, purple (p long), the 
flowers hairy toward the base. It (Poa fh\va, L.! P. seslerioides, 
Michx. P. quinquefida, Pursh. Windsoria poaeformis, Jhfutt.) — Dry 
or sandy fields, S. New York and southward. Aug. — A showy 
grass, with the spreading panicle sometimes 1° wide. Points of the 
lower palea almost equal, scarcely exceeding the intermediate teeth, 
thus appearing 5-toothed. 
§2. Triplasis, Beauv. (Diplbcea, Raf. Ur&lepis, Nutt.) — Glumes 
much shorter than the somewhat remote Jlowers: both palea strongly 
fringe-bearded ; the lower 2-cleft at the summit , the mid-nerve produc¬ 
ed into an awn between the truncate or awn-pointed divisions. 
2- T. purpurea. (Sand Grass.) Culms many in a tuft from 
the same root, ascending (6'-12' high), with numerous bearded joints; 
leaves involute-awl-shaped, mostly short; panicles very simple, bear¬ 
ing few 2- 5-flowered spikelets, the terminal one usually exserted, the 
axillary ones included in the commonly hairy sheaths; awn much 
shorter than the palea , frequently not exceeding its eroded-truncate or 
obtuse lateral lobes. 0? (Aira purpurea, If alt. Diplocea barbAta, 
R (, f- Uralepis purpurea and aristuLta, Jfutt.) —In sand, from Con- 
50 
