GRAMINE.E. (GRASS FAMILY.) 579 



waste grounds, Florida to North Carolina. July -Sept. Q) — Culms l°-2° 

 long. Involucre purplish. 



2. C. tribuloides, L. Involucres whitish, 10-15 in a spike, wedge-shaped 

 at the base, armed above with stout compressed broadly subulate erect or spread- 

 ing spines ; bristles none ; spikelets mostly by pairs. — Sands along the coast, 

 Florida, and nortli ward. July - Oct. (j) — Culms prostrate, 1 ° - 2° long. Leaves 

 linear. Spikes I' -2' long. 



52. STENOTAPHRUM, Trin. 



A creeping and branching grass, with the awnless spikelets sunk in excavations 

 of the continuous flattened i-achis. Spikelets by pairs, one pedieelled and imper- 

 fect, the other sessile, and with the structure of Panicum. 



1. S. Americanuni, Schrank. (Rottboellia dimidiata, Ell.) — Damp 

 sandy places along tlie coast, Florida to South Carolina. June - Sept. y. — 

 Smooth throughout. Culms flattened, creeping, the branches nearly opposite ; 

 flowering culms erect, 6'- 12' high. Leaves 2' -6' long, linear, obtuse, flat or 

 folded, contracted at the base. Spikes lateral and terminal, peduncled, 2' - 5' 

 long. Sterile spikelet neutral or rudimentary. Fertile spikelet sessile; the up- 

 per glume 7-nerved, 3 times the length of the lower one. Palea of the sterile 

 flower coriaceous, like those of the perfect one. 



53. E-OTTBCELLIA, Brown. 



Erect perennial mostly tall grasses, with flat or channelled leaves and spiked 

 inflorescence. Spikes nearly terete, jointed. Spikelets awnless, borne by pairs at 

 the base of each joint ; one imperfect, on a coriaceous and closely appressed ped- 

 icel ; the other sessile, embedded in an excavation of the joint, 2-flowered. Glumes 

 2, the exterior one flat, coriaceous, with a hinge-like depression at the base, the 

 interior boat-shaped, membranaceous. Palea; hyaline, 1 -2 in the staminate or 

 neutral lower flower, and 2 in the upper and perfect flower. Stamens 3. Styles 

 2. Grain compressed, free. — Spikes solitary on lateral and terminal peduncles 

 or branches. 



1. R. rugosa, Nutt. Culms compressed ; peduncles or branches clustered, 

 short, included in the sheaths of the elongated upper leaves ; spikes spreading, 

 slightly compressed ; sessile spikelet shorter than the joint; lower glume lance- 

 olate, transversely rugose ; sterile flower neutral. — Pine-barren swamps and 

 ponds, Florida to North Carolina. Sept. — Culms 2° -4° high. Spikes green, 

 lJ'-2' long, 1" in diameter. 



2. R. corrugata, Baldw. ? Culm stout, compressed ; peduncles mostly 

 single, elongated; spikes slightly compressed, erect; spikelets longer than the 

 joint; lower glume longitudinally grooved and somewhat reticulated, ovate; 

 sterile flower staminate. — Low pine l)arrens, Georgia and Florida, near the 

 coast. Sept. and Oct. — Culm 2° -4° high. Spikes 4' -6' long, 2" in diam- 

 eter, purplish. 



3. R, cylindrica. Culm slender, terete ; leaves narrowly linear ; peduncles 

 single, elongated; spikes slender, terete, mostly curved; spikelets as long as 



