56 POACEAE 
8. Erianthus Smállii Nash. Stems 1.5-2.5 m. tall, the nodes pubescent with readily 
deciduous hairs, the summit and the panicle-axis copiously appressed-pubescent with long 
silky hairs. Leaf-sheaths usually sparingly hirsute at the apex, otherwise glabrous ; blades 
1.5-7 dm. long, 6-20 mm. wide, rough on both surfaces: panicle 2-4 dm. long, 4-6 cm. 
wide, its branches erect, the larger 7-10 cm. long: spikelets crowded, about equalling the 
basal hairs and 3 again as long as the internodes ; 2 outer scales 8-9 mm. long, pilose with 
long hairs ; fourth scale 2-toothed at the apex, the teeth long and subulate, the awn 2-2.5 
em. long, the included portion long and tightly spiral, the remainder loosely spiral. 
In low grounds, Tennessee to Georgia, Florida and Mississippi. Fall. 
9. Erianthus strictus Baldw. Stems 1-2 m. tall, the nodes usually pubescent with 
readily deciduous hairs, the summit and the panicle-axis glabrous. Leaf-sheaths glabrous ; 
blades 2-7 dm. long, 5-10 mm. wide, rough on the margins but otherwise smooth : pan- 
icle 2-4 dm. long, 1-2 cm. wide, its branches appressed, the larger 5-8 cm. long : spikelets 
crowded, about 4 again as long as the internodes, the basal hairs wanting or sparse and less 
than } as long as the spikelet ; 2 outer scales 8-10 mm. long, strongly appressed-hispid ; 
fourth scale entire or shortly 2-toothed at the apex, the awn 1.5-2 cm. long, straight. 
In moist soil, Tennessee to Florida and Texas. Fall. 
4. MANISURIS L. 
Perennial, often tall grasses, sometimes with rootstocks, narrow flat leaf-blades, and 
cylindric articulated terminal and axillary spikes. Spikelets in pairs at each joint, in ex- 
cavations in the rachis, one sessile and containing a perfect flower, the other pedicellate 
and either bearing a staminate flower, or empty. Scales of the sessile spikelet 4, the 
outermost thick and coriaceous, sometimes more or less rugose or pitted, concealing, to- 
gether with the pedicel of the other spikelet, the remaining scales and the excavation in 
the rachis ; second scale chartaceous, the third and fourth scales hyaline, the former empty 
or infolding a staminate flower, the latter enclosing a thinly hyaline palet and perfect 
flower. Scales of the pedicellate spikelet 4 or fewer. Stamens 3. Styles distinct. 
[ Rottboellia L. f.] RAT-TAIL Grass. 
Stems from horizontal rootstocks, round ; sheaths round, narrow. 1. M. cylindrica. 
Stems tufted, much flattened, at least below ; rootstocks wanting ; sheaths much com- 
pressed, broad, keeled. 
First scale of the sessile spikelet transversely wrinkled (rarely smooth). 
Wrinkles short, but little elevated, tubercle-like, sometimes entirely wanting. 2. M, tuberculosa. 
Wrinkles long, often extending completely across the scale, much elevated. 
Leaf-blades rather short and broad, especially those of the upper sheaths, 
6-10 mm. wide at the base: rachis of the racemes glabrous. 3. M. C hapmanii. 
Leaf-blades elongated and narrow, even those of the upper sheaths, 6 mm. 
wide at the base or less: rachis of the racemes puberulent. 4. M. rugosa. 
First scale of the sessile spikelet pitted. 5. M. tessellata. 
1l. Manisuris cylíndrica (Michx.) Kuntze. Stems from creeping rootstocks, round, 
3-10 dm. tall, slender: leaf-sheaths round, narrow ; blades 3 dm. long or less, 1-3 mm. 
wide: racemes finally exserted, 1-2 dm. long, straight or curved, the rachis barely if at all 
contracted at the nodes: sessile spikelet 4.5-5 mm. long, about equalling the internode, 
the first scale more or less pitted in longitudinal lines, or rarely unpitted, each pit often con- 
taining a subulate hair; pedicellate spikelet reduced to 1 or 2 short scales, the pedicel 
linear, shorter than the sessile spikelet and curved around its margin. [Rottboellia cylin- 
drica (Michx.) Chapm.] 
In sandy soil, Georgia and Florida to Texas; also in Missouri and the Indian Territory. Summer, 
2. Manisuris tuberculósa Nash. Stems tufted, much compressed, 8-12 dm. tall, 
stout: leaf-sheaths much flattened, broad, keeled; blades 3 dm. long or less, 3-7 mm. 
wide: racemes finally exserted, 6-10 cm. long, straight, the rachis barely if at all contracted 
at the nodes : sessile spikelet about 4 mm. long, about equalling the internode, the first 
scale transversely wrinkled, or very rarely without wrinkles, the wrinkles short, tubercle- 
like, irregularly disposed ; pedicellate spikelet reduced to 1 or 2 short scales about 4 the 
length of the linear pedicel which isa little shorter than the sessile spikelet and curved 
around its margin. 
On lake shores, peninsular Florida. Summer. 
3. Manisuris Chapmánii (Hack.) Nash. Stems tufted, 6-15 dm. tall, much com- 
pressed: leaf-sheaths much flattened, broad throughout ; blades usually less than 2.5 dm. 
long, 6-10 mm. wide, those of the inflorescence generally very short and broad : racemes 
commonly 4-5 em. long, occasionally longer, little compressed, exserted or a little included 
at the base, the rachis glabrous, the internodes and pedicels usually flat, not much de- 
pressed on the back: sessile spikelet 4-5 mm. long, usually exceeding the stout inter- 
