GRAMINEJE. (GRASS FAMILY.) 603 







sometimes permanently adherent to, the palets. A vast and most impor~ 

 tant family, as it 'furnishes the cereal grains, and the principal food of cat- 

 tle, &c. (See Plates 7 - 14.) 



Tribe I. POACE.3E. R. Br. Spikelets 1 - many-flowered, when more than one-flowered 

 centripetal in development ; the lowest flowers first developing, uppermost, if any. imper- 

 fect or abortive, the rest all alike in the spikelet (perfect, or occasionally monoecious or dioe- 

 cious) ; only in a few exceptional cases with the lowest of the several flowers less perfect 

 than the upper (viz. staminate only in Arrhenatherum and Phragmites, neutral in Uniola, 

 Gtenium, &c.). 



Subtribe 1. Oryzete. Spikelets 1-flowered, in panicles, the flowers often monoecious. 

 Glumes abortive or wanting ! Inner paleae 3-nerved ! Stamens 1-6. 



1. Leersla. Flowers perfect, strongly flattened contrary to the awnless conduplicate palets. 



2. Zizaiiia. Flowers monoecious. Palets convex ; the lower one awned in the fertile flowers. 



Subtribe 2. Agrostideee. Spikeleta 1-flowered, perfect, and occasionally with the 

 rudiment or abortive pedicel of a seconbl flower above, panicled, or clustered, sometimes so 

 contracted as to form a sort of spike, but the Spikelets are not directly borne on the 

 common axis. Stamens 1-3. 



* PHLEOIDEjE. Glumes equal, strongly keeled, laterally flattened, boat-shaped, somewhat 



herbaceous, as well as the paleae. Inflorescence densely spiked ! 



3. Alopecurus. Glumes united at the base. Lower palet bearing an awn on the back : 



the upper palet wanting. 



4. Phleum. Glumes distinct, sharp-pointed, much larger than the two thin and truncate 



awnless palets. 



5. Crypgis. Glumes distinct, not longer than the palets ; both awnless and pointless. 



* * AGROSTIDEJE proper. Glumes and palets both membranaceous, or the latter sometimes 



very thin and delicate. Inflorescence panicled or glomerate, sometimes rather spike-like, 

 but not contracted into a uniform cylindrical spike. Palets not surrounded by a tuft of 

 hairs, or only with some very minute ones at the base. 



*- Flower perfectly sessile in the glumes : lower palet 1-nerved : awns none. 



6. Vilfa. Fruit a caryopsis (seed adherent to the pericarp, as in most grasses). Panicle 



spiked or contracted. 



7. Sporobolus. Fruit an utricle (seed loose in the thin pericarp). Panicle open or close. 

 +- - Flower slightly raised in the glumes on a short sometimes stalk-like base (callus") : lower 



palet 3 - 5-nerved ; and this or the glumes awned or pointed, except in some species of No. 8. 



8. Agrostis. Glumes equal, or the lower one rather longer, pointless, exceeding the very 



thin blunt palets. Lower palet pointless, often awned on the back ; the upper sometimes 

 wanting. Panicle open. 



9. Poly pogon. Glumes nearly equal, long-awned, much longer than the palets, the lower 



of which is often short-awned below the apex. Stamens 3. Panicle contracted. 



10. Cinna. Glumes acute, the lower about equalling and the upper slightly exceeding the 



similar palets. Stamen 1. Flowers raised on a distinct naked stalk, beardless : lower 

 palet short-awned or bristle-pointed just below the tip ; ttie upper 1-nerved. 



11. Mublenbergia. Lower glume mostly smaller. Palets chiefly hairy-bearded at the 



base, the tip of the lower one mucronate-pointed or awned. Stamens 3. 



12. Brachyelytrum. Lower glume almost obsolete, and the upper minute. Lower palet 



long-awned from the tip ; the upper grooved on the back and bearing a long and slender 

 naked pedicel of an abortive second flower. Stamens 2. 



* * * CALAMAGR.OSTIDE.ffi. Flower with a copious tuft of hairs at the base of the palets : 



otherwise as in the foregoing subdivision. 



13. Calamagrostis. Lower palet mostly awned on the back, shorter than the glumes. 



