POACEAE 63 
scale, the pedicel considerably exceeding the sessile spikelet. [A. Virginicus var. tetra- 
stachyus ( Ell.) Hack.] 
In dry or moist soil, South Carolina to Florida and Alabama. Fall. 
10. Andropogon Mohrii Hack. Stems 8-12 dm. tall: leaf-sheaths densely ap- 
pressed-hirsute ; blades 3 dm. long or less, 5 mm. wide or less, densely appressed-hirsute : 
spathes 4-5 em. long, equalling or a little shorter than the racemes : racemes in 4’s, 3-4 
cm. long, rather stout, the hairs at the summit of the rachis-internodes 3 again as long as 
the spikelets: sessile spikelet about 4.5 mm. long, about twice as long as the internode, 
the awn straight or nearly so, slightly if at all twisted at the base, 2-2.5 cm. long ; pedicel- 
late spikelet wanting, or sometimes present as a small subulate scale, the pedicel usually a 
little shorter than the sessile spikelet. 
In low pine lands, western Florida to Louisiana. Fall. 
11. Andropogon gracílior (Hack.) Nash. Stems tufted, slender, 3-7 dm. tall, 2-3 
times as long as the basal leaves, the lower branches single: leaf-sheaths glabrous, shorter 
than the internodes, the terminal ones more or less enlarged, 5-7 cm. long, 2-3 mm. wide ; 
stem-leaves with blades 1.5 dm. long or less, 1-2 mm. wide, smooth beneath, rough above 
and sparingly hirsute near the base : racemes in pairs, slender, about 3 cm. long, exserted, 
or slightly included at the base: sessile spikelet 3.5-4 mm. long, equalling or somewhat 
exceeding the internode, the awn geniculate, 1.3-2 cm. long, loosely spiral at the base, the 
column exserted ; pedicellate spikelet a minute rudimentary scale, the pedicel usually about 
3 again as long as the sessile spikelet. 
In dry or moist places, Florida to Alabama; also in Tennessee. Fall. 
12. Andropogon Ellidttii Chapm. Stems tufted, 5-8 dm. tall, rather stout, 2-3 
times as long as the basal leaves: leaf-sheaths shorter than the internodes, the lower ones 
and those of the innovations densely appressed-hirsute, those of the inflorescence much en- 
larged and densely crowded at the summit and also sometimes at the nodes below, 8-11 cm. 
long, 3-6 mm. wide; blades 2 dm. long or less, 2-5 mm. wide, usually smooth beneath, 
rough above and hirsute near the base : racemes in pairs, slender, 3-4 cm. long, the longer 
one at each node exserted, the rest concealed in the spathes: sessile spikelet 4.5-5 mm. 
long, equalling or somewhat exceeding the internode, the awn geniculate, 1.5-2.3 cm. long, 
usually spiral at the base, the column much exserted ; pedicellate spikelet a minute rudi- 
mentary scale, the pedicel usually about 4 again as long as the sessile spikelet. 
In dry sandy soil, South Carolina and Tennessee to Florida and Mississippi. Fall. 
13. Andropogon campylorácheus Nash. Stems densely tufted, 4-8 dm. tall, the 
terminal internode much elongated and slender, the branches single : leaf-sheaths much 
exceeding the internodes, overlapping, those on the stem 13-17 em. long, sparingly hirsute, 
those on the innovations densely hirsute with ascending hairs, the terminal one very nar- 
row and tightly embracing the stem, the upper sheaths on some of the stems much en- 
larged and producing smaller spathes in their axils with concealed racemes ; blades erect, 
2 dm. long or less, 2-3 mm. broad, smooth beneath, hirsute above near the base : racemes 
in 2's-4's, flexuous, 5-10 cm. long: sessile spikelet 5 mm. long, usually much exceeded 
by the internode, the terminal hairs of which are 8-10 mm. long, the awn more or less 
contorted, 1.5-2 cm. long, barely if at all twisted at the base ; pedicellate spikelet wanting, 
or present as a minute rudimentary scale, the pedicel much exceeding the sessile spikelet. 
In dry sandy soil, southern peninsular Florida and Mississippi. Fall. 
14. Andropogon brachystáchyus Chapm. Stems tufted, 6-15 dm. tall, the 
branches in l's-3's and usually pilose just below the nodes: leaf-sheaths smooth and 
glabrous; blades erect, 3 dm. long or less, 3-4 mm. wide, smooth beneath, on the upper 
surface rough and hirsute near the base: racemes in pairs, shortly exserted, or partly in- 
cluded at the base, 1-2 cm. long: sessile spikelet 3~4.5 mm. long, about twice as long as 
the internode, the first scale pubescent between the keels, the awn of the fourth scale 
straight or nearly so, 6-9 mm. long; pedicellate spikelet consisting of a single scale, the 
pedicel shorter than the sessile spikelet. 
In moist pine lands, Florida. Summer and fall. : 
15. Andropogon Floridanus Scribn. Stems tufted, 5-16 dm. tall, the branches in 
1’s~3’s : leaf-sheaths roughish, usually shorter than the internodes; blades 5 dm. long or 
less, 1 em. wide or less, rough : racemes in pairs, occasionally in 3's or 4’s, 3-4 cm, long, 
exserted, or partly included at the base : sessile spikelet 3.5-4 mm. long, equalling ora little 
longer than the internode, the awn straight, 8-12 mm. long ; pedicellate spikelet wanting 
or present as a small scale, the pedicel exceeding the sessile spikelet. 
In dry pine lands, peninsular Florida. Summer and fall. 
16. Andropogon subténuis Nash. Stems 3-6 dm. tall, slender, the branches single : 
leaf-sheaths smooth and glabrous; blades 1.5 dm. long or less, 1-2 mm. wide, smooth 
