T 
l. BE. tripsacoides H.B.K. (Andropogon Nuttalli Chapm.; Rottbelia ciliata Nutt.) 
(Chapu:., FloraS. U. States, p.580.) Culms 3 to 4 feet high, stout, erect, smooth; leaves 
linear, smooth; spikes terminal and lateral, 3 to 5 inches long, on long peduncles; 
rachis and pedicel of sterile flower white-ciliate; outer glumes hispid-ciliate near the 
margin.—Florida to Texas and Mexico, 
2. B. barbiculmis Hack. (Andropogon candidus Torr. in Herb.) (Vasey, Grasses of 
the Southwest, Pl. 15.) Culms 2 to 3 feet high, white-ciliate at the nodes, pubescent 
below, more slender than the preceding; radical leaves numerous, almost capillary, 
about half as long as the culm, ciliate-margined; spikes mostly terminal, 3 to 4 inches 
long; rachis, pedicels, and first and second glumes white villous.—Texas, Arizona 
and Mexico. 
ROTTBCULLIA Linn. f. 
Culms erect, spikes terminal, or terminal and lateral, cylindrical 
or slightly compressed, joints of the rachis and pedicels thickened, first 
or outer empty glume coriaceous, covering the excavation in the rachis, 
joints of rachis and spikelet usually naked. 
(a) Joints of rachis readily disarticulating. 
1. R. cylindrica Chapm. (Tripsacum cylindricum Michx.) (Chapm. FI, S. States, 
p- 579.) Culms slender, terete, 1 to 2 feet high; leaves narrowly linear; spikes mostly 
terminal and curved, 2 to 6 inches long, 1 line in diameter, purplish; spikelets as 
long as the internode; lower glume obtuse, obscurely pitted, sterile spikelet rudi- 
mentary.—Florida to Texas, 
2. R. rugosa Nutt. (Chapm. FI. 8. States, p. 579.) Culms compressed, 2 to 4 
feet high, smooth; leaves long, linear spikes numerous (5 to 15), mostly on long 
pedicels 2 to 6 inches long; spikelets sessile, about equaling the joints; lower empty 
glume transversely rugose and sometimes reticulated.—Delaware, Florida to Texas. 
3. R. corrugata Baldw. (Chapm. FI. 8, States, p. 579.) Peduncles mostly single, 
elongated; spikes slightly compressed, erect; spikelets longer than the joint.— 
Southern States, near the coast. 
Var. AREOLATA Hack.—Alabama (Dr. Charles Mohr). 
(6) Joints of rachis persistent or tardily disjointing. 
4, R. fasciculata Lam, Ill. 1. 204. (Hemarthria fasciculata Kth.) Culms angular 
or compressed, 2 to 3 feet high; leaves short; spikes mostly fassicled, 2 to 4 inches 
long, compressed, not rigid, from numerous lateral branches; pedicel of the stam- 
inate spikelet adnate to the rachis,—Southwestern Texas (Havard, Nealley). 
MANISURIS Swartz. 
Spikelets small, in pairs; the sessile or perfect spikelet 1-flowered, 
globose, inflated, pitted externally; the pedicellate spikelets flat, male 
or empty, their pedicels grown to the rachis. 
1. M. granularis Swartz. (Chapm. FI. 8. States, p. 580.) Culms 1 to 24 feet 
high; much branched below; leaves 1 to 4 inches long, the sheaths pubescent or 
scabrous, inflated, blade ciliate on the margins; spikes numerous, lateral and ter- 
minal, about | inch long, closely flowered ; spikelets less than 1 line long.—Florida to 
Texas and Mexico, near the coast. 
TRACHYPOGON Nees. 
Spikes or spikelike raceme solitary and terminal. Axis of the spikes 
indistinctly articulate, not brittle, the male spikelet very short-pedi- 
celed, awnless; fertile spikelet longer-pediceled, and with a long twisted 
and bent awn. 
2 
a. 
