GRAMINEiE. 



413 



Order CXXV. GIIAMINE^. Juss. The Grass Tribe. 



Flowers in small spikelets, consisting of bracts or scales imbricated in 2 rows, 

 the exterior of which (usually 2) are called glumes, and the two that imme- 

 diately inclose the flower, palece. Calyx and corolla none, or reduced to minute 

 scales or lodiculte, which are usually 2 in number. Stamens mostly 3 : anthers 

 versatile. Styles 2, sometimes united at the base : stigmas feathery. — Stems 

 C culms ) hollow, closed at the joints. Sheaths of the leaves split, or open on one 

 side (very rarely entire), often furnished with a membranaceous appendage 

 (ligule) on one side. 



CONSPECTUS OF THE TRIBES AND GENERA. 



Tribe 1. ORYZEjE. Spikelets either one-flowered, with the glumes mostly abortive ; or 2 - 3-flowered, one or 

 both of the lower flowers with a single palea and neuter, the terminal one fertile. Palea; somewhat 

 coriaceous. — Flowers mostly hcxandrous. 



1. Leersia. Spikelets one-fl owered. Glumes none. Palcje 2, awnless. 



2. Zizania. Monoecious. Spikelets one-flowered. Glumes none. Palea) of the pistillate flowers awned, membrana- 



ceous. 



Tribe 2. PHALARIDEiE. Spikelets perfect, polygamous or rarely monoecious : either one-flowered, without a 

 rudimentary stipc-likc flower ; or 2-flowered, the flowers perfect or sterile ; or 2 - 3-flowered, the 

 terminal flower perfect, the others incomplete. Palea; mostly indurated in fruit. 



3. Alopecurus. Spikelets one-flowered. Glumes 2, awnless, boat-shaped, united above the base. Upper palea want- 



ing : lower one awned on the back. 



4. Phleum. Spikelets one-flowered. Glumes distinct, boat-shaped. Paleae awnless. 



5. Phalaris. Spikelets 3-flowered, awnless ; the 2 lower flowers scale-like ; upper flower perfect. Glumes 2, keeled. 



6. Hoi.cus. Spikelets 2-flowered : glumes nearly equal ; lower flower perfect, awnless ; upper one staminate or neuter ; 



the lower pales awned on the back. 



7. Hierochloa. Spikelets 3-flowered ; the two lower flowers staminate, triandrous, awned ; uppermost flower dian- 



drous, awnless. 



8. Anthoxa.vthum. Spikelets 3-flowered ; the two lower flowers neuter, each consisting of a single awned palea ; 



upper flower perfect, awnless, diandrous. 



Tribe 3. PANICEjE. Spikelets 2-flowered; the lower flower incomplete, usually neuter. Glumes of thinner 

 texture than the palea ; the lower one often (rarely both) abortive. Palea; more or less coriaceous, 

 commonly awnless ; the lower one concave. 



9. P asp alum. Glume single. Lower flower neuter, of a single palea, membranaceous. Perfect flower of 2 awnless 



palea;. — Flowers in spikes ; the pedicels jointed. 



10. Milium. Glume single. Lower flower neuter, of a single palea. Perfect flower awnless. — Flowers in a loose 



panicle ; the pedicels not articulated. 



11. Panicum. Spikelets naked : glumes 2, very unequal. Lower flower of one or two palex. 



13. Pennisetum. Spikelets with an involucre of several distinct bristles, 2-flowered : glumes two, unequal. Lower 

 flower of one or two palea;. 



13. Cenciirus. Spikelets enclosed in an indurated involucre, which is spiny or bristly externally. Glumes 2. 



Tribe 4. STIPACEjE. Spikelets one-flowered. Lower palea involute, with a simple or 3-cleft mostly twisted 

 awn at the tip, indurated in fruit. Ovary stipitate. 



14. Or^zopsis. Glumes 2, membranaceous, nearly equal, awnless. Paleaj coriaceous, equal in length : awn deciduous, 



straight. Scales linear, elongated. Stipe of the ovary short. 



