GKAMINEJE. (gRASS FAMILY.) 539 



Tbibb ni. PXyiCEJE, Spikelets 2-flowered ; the lower flower always imperfect, either 

 Btaminate or neutral ; in the latter case ustially redaced to a single empty valve (placed 

 next the lower glume, if that be present) ; the upper (terminal) flower (placed next ttie 

 upper or inner glume) only fertile Embryo and groove (when present) on the outer 

 aide of the grain I (next the lower valve of the fertile flower). (Flowers polygamous, or 

 hemigamous (when the lower flower is neutral), or Bometimes seemingly simple and per- 

 feet, from the suppression both of the lower glume and of the upper palea of the neutral 

 flower, sometimes monoecious, or rarely dioeciouB. Rarely both glumes are wanting.) 



Subtribe 1. Pabpalk£, Griseb. Qlui^es and sterile paleae herbaceous or membranaceous : 

 paleae of the fertile flower of firmer texture, coriaceous or chartaccous. awnless, not 

 keeled, more or less flattened parallel with the glumes. 



• Spikelets appearing as if simply 1-flowered from the suppression of the lower glume ; the sin- 



gle neutral palea of tbe sterile flower apparently occupying its place. (Awnl^s.) 

 56 MILIUM. Spikelets not jointed with their pedicels, all alike in a terminal open panicle. 

 57. AMPHIUARPUM. Spikelets jointed with their pedicels, of 2 eorte ; one in a terminal pan- 

 icle ; the other subterranean, on radical peduncles. 

 68 PASPALUM. Spikelets jointed with their short pedicels, all alike, plano-convex, in one- 

 sided spikes or spiked racemes. 



• * Spikelets manifestly 1^ - 2-flowered (polygfunous, the lower flower staminate or often neu- 



tral), the lower glume being present. 



59. PANICUM. Spikelets not involucrate, nor the peduncles bristle-bearing. Lower glume 



small or minute Sterile flower either staminate or neutral. 



60. SETARIA. Spikelets spiked-panicled, the peduncles continued into naked solitary bristles : 



otherwise as in Fanicum. 



61. CENCHRUS Spikelets enclosed 1-5 together in a hard and spiny globular bur-like invo- 



lucre. 



Subtribe 2. Sacokare^, Fertile palesD membranaceous or scarious, always of thinner and 

 more delicate texture than the (often indurated) glumes, freq.uently awned from the tip. 

 Spikelets usually in pairs or threes, panicled or spiked, some of them entirely sterile 

 (heterogamous). 



* Spikelets monoecious, imbedded in the separable joints of the spike. 



62. TRIPS ACUM. Staminate spikelets above, in pairs at each joint : pistillate single in each 



joint : glumes indurated. 



• * Fertile spikelets with one perfect and one sterile (staminate or mostly neutral) flower : low- 



er palea of the perfect flower awned. 



63. SRTANTQUS. Both spikelets at each joint of the rbachis aUke fertile, involucrate with a 



silky tuft : otherwise aa No. 64. 



64. ANDROPOGON^ Spikelets 2 at each joint of the plumose-hairy spikes, one of them sessile 



and fertile ; the other pedicelled and sterile or rudimentary. 

 65 SORGHUM. Spikelets in open panicles, 2-3 together, the lateral ones sterile or sometimes 

 reduced to mere pedicels. 



1. liEERSIA, Solander. False Ricb. White Gkass. 



Spikelets 1-flowered, perfect, flat, crowded in one-sided panicled spikes or 

 racemes, more or less imbricated over each other, jointed with the short pedicels. 

 Glumes wanting. Paleae chartaceous, much flattened laterally, boat-shap»d, 

 awnless, bristly-eiliate on the keels, closed, nearly equal in length, but the lower 

 much broader, enclosing the fiat grain. Stamens 1-6. Stigmas feathery, the 

 hains branching. — Perennial marsh grasses : the flat leaves, sheaths, &c., rough 

 upwards (especially in No. I), being clothed with very minute hooked prickles. 

 (Named after Leers, a Gcraian botanist.) 



