HITCHCOCK—GRASSES OF CUBA. 189 
Series Poacear.—Spikelets 1 to many-flowered, the imperfect or rudimentary 
floret, if any, uppermost; rachilla articulated (except in Oryzeae) above the glumes, 
which are persistent on the pedicel or rachis after the fall of the florets; when 2 to 
many-flowered a manifest internode of the rachilla separating the florets and articu- 
lated below them; spikelets laterally compressed. 
Spikelets articulated below the glumes. (ORYZEAE.) 
Spikelets unisexual, plants monoecious. 
Spikelets in pairs, one large, perfect, sessile, the other small, staminate, long- 
-pediceled; the broad oblanceolate blades with transverse veins between 
the longitudinal nerves.........-.-.-..-.++0+0------ 45. Pharus (p. 234). 
Spikelets not in pairs, the staminate and pistillate in different panicles, 
blades linear, not cross-veined ............-.------ 46. Luziola (p. 234). 
Spikelets all perfect. . 
Glumes wanting, lemma awnless.........-.-- 48. Homalocenchrus (p. 234). 
Glumes present. 
Glumes minute, awnless; lemma awned except in cultivated forms. 
47. Oryza (p. 234). 
Glumes about as long as the floret or longer, awned. 
Glumes tapering into awns; spikelets, including awns, over 3 cm. 
long... 2.2... 2220-2222 49, Achlaena (p. 235). 
Glumes awned from the notched apex; spikelets, including awns, 
scarcely 1 cm. long.........-----+------ 50. Reynaudia (p. 235). 
Spikelets articulated above the giumes. 
Culms woody, perennial, at least at the base, leaf blades commonly articulated 
with and deciduous from the sheath. (BAMBUSEAE.) 
66. Arthrostylidium (p. 245). 
Culms herbaceous, annual, leaf blades not articulated with the sheath. 
Inflorescence of l-sided spikes or racemes, spikelets sessile or nearly so. 
(CHLORIDEAE.) 
Plants dioecious or moncecious, the staminate awnless, pistillate with 
numerous awns; low stoloniferous grass......... 60. Opizia (p. 242). 
Plants not dicecious, spikelets all alike. 
Spikelets with 1 perfect floret, sometimes 1 or more sterile florets 
above the perfect one. 
No sterile florets, spikelets awnless, spikes slender, digitate. 
54. Capriola (p. 238). 
One or two sterile florets above the perfect one, spikelets gen- 
erally awned. 
Spikes digitate or approximate in apparent whorls at the 
summit of the culm..........-.----- 55. Chloris (p. 238). 
Spikes remote along the main axis. .56. Bouteloua (p. 240). 
Spikelets with 2 or 3 perfect florets. 
Spikes alternate, more or less remote along the main axis, spike- 
lets not crowded..........-..--+-------99. Leptochloa (p. 241). 
Spikes digitate or nearly so, spikelets crowded. 
Axis of spike not produced beyond the uppermost spikelet, 
glumes and lemmas not cuspidate...57, Eleusine (p. 241). 
Axis of spike produced into a naked cuspidate point, glumes 
and lower lemmas cuspidate.58. Dactyloctenium (p. 241). 
Inflorescence paniculate, sometimes contracted but spikelets never sessile in 
1-sided spikes. 
Spikelets 1-flowered. (AGROSTIDEAE.) 
Lemma awnless...........-.-0--2e22 eee ees 53. Sporobolus (p. 237). 
