40 



GRAMINEAE (GRASS FAMILY) 



Tribe in. PANICEAE 

 Splkelets without a subtending involucre of bristles or valves. 

 Spikelets in one-sided racemes or spikes. 



First glume well developed 6. Paspalum. 



First glume small or abortive. 



' Plant annual 7. Syntherisma. 



Plant perennial 8. Brachiaria. 



Spikelets not in one-sided racemes or spikes. 



Glumes awned 9. Echinochloa. 



Glumes not awned 10. Panicum. 



Spikelets involucrate. 



The involucre consisting of bristles 11. Chaetocbloa. 



The involucre consisting of spine-bearing valves forming a bur . 12. Cencbrus. 



Tribe IV. ORYZEAE 

 Flowers perfect; glumes wanting . 13. Homalocenchrut 



Tribe V. PHALARIDEAE 



Uppermost floret perfect, the others empty 14. Phalaris. 



Uppennost floret perfect, the others staminate .... 16. Hierochloe. 



Tribe VI. AGROSTIDEAE 



Lemma with a long terminal awn, and closely embracing the grain. 

 Spikelets not in pairs. 



Fruiting lemma thin and membranous 20. Muhlenbergia. 



Fruiting lemma firm, and indurated. 



Awns 3-branched 16. Aristida. 



Awns simple. 



Twisted, persistent on the lemma 17. Stipa. 



Straight, deciduous from, the lemma. 



Lemma glabrous or appressed-pubescent . . . 18. Oryzopsis. 



Lemma long silky-pubescent 19. Eiiocoma. 



Spikelets paired, in a spike-like raceme 21. Lycurus. 



Lemma awnless or short-awned, and loosely investing the grain. 

 Inflorescence a dense spike. 



Spikelets persistent; lemma awnless or with a short terminal awn. 



Spikes cylindrical 22. Phletun. 



Spikes ovoid 27. Polypogon. 



Spikelets early deciduous; lemtma with a dorsal awn . . 23. Alopecurus. 

 Inflorescence a loose panicle. 



Pericarp discharging the seed at maturity, 



A diminutive alpine perennial ...... 24. Phippsia. 



Larger and mostly at middle and lower altitudes. 



Nerves of lemma not pilose ...... 26. Sporobolus. 



Nerves of lemma pilose » 26. Blepharineuron. 



Pericarp permanently investing the seed. 



Palet 1-nerved; stamen 1 28, Cinna. 



Palet 2-nerved; stamens 3, 



Lemma naked at the base 29« Agrostis. 



Lemma with a tuft of long hairs at the base. 



Thin-membranous 30. Calamagrostis. 



Chartaceous 31. CalamovUfa. 



Tribe VD. AVEITEAE 



Awn of the lemma dorsal. 



Spikelets less than 1 cm. long. 



Lemma erose-truncate 32. Deschampsia. 



Lemma 2-toothed, with awn twisted and bent .... 33. Trisetum. 



Spikelets more than 1 cm. long 36. Avena. 



Awn of the lemma terminal, between the teeth . , . 36. Danthonia. 



