146. Gramineae 325 



9. Spikelets 8-20-flowered, green, nodding on long slender pedicels, 

 the lower 1-5 lemmas sterile 11. Uniola 



9. Spikelets 2- or 3-flowered, short-pedicelled, the uppermost 1-3 



sterile lemmas much smaller 15. Melica 



8. Spikelets without sterile lemmas. 



10. Lemmas awned. 



11. Lemmas bifid at apex, awned just below the apex or behind 

 the teeth. 

 12. Ovary pubescent at apex; grain furrowed, adnate to the 

 palet; stigmas sessile, arising below the apex of the 



ovary; sheaths closed 2. Bromus 



12. Ovary glabrous; grain smooth, free; styles terminal; 



sheaths split 3. Schizachne 



11. Lemmas entire, with an apical point or awn 4. Festuca 



10. Lemmas awnless, or mucronate, or short-awned in Dactylis. 



13. Spikelets nodding, as broad as long, on capillary pedicels in 

 open panicles; lemmas papery, imbricated, scarious- 



margined, cordate at base, the apex obtuse or acutish 



8. Briza 



13. Spikelets not as above in all respects. 



14. Spikelets strongly flattened, crowded in 1-sided clusters 

 at the ends of long branches; keels of the glumes and 



lemmas hispid-ciliate 12. Dactylis 



14. Spikelets neither strongly flattened, nor in 1-sided 

 clusters. 



15. Lemmas with cobwebby hairs at base 7. Poa 



15. Lemmas without cobwebby hairs. 

 16. Nerves of the lemma parallel. 



17. Lemmas faintly 5-nerved; stigmas sessile, the 

 style none; sheaths open; annual or peren- 

 nial halophytes 5. Puccinellia 



17. Lemmas prominently 5-9-nerved; styles short, 



distinct; sheaths closed; tall marsh peren- 

 nial grasses 6. Clyceria 



16. Nerves of the lemma converging at the apex 

 (sometimes indistinct). 



18. Lemmas 8-11 mm long; spikelets large 



2. Bromus 



1 8. Lemmas less than 8 mm long. 



19. Lemmas keeled on the back, the apex ob- 

 tuse or acute 7. Poa 



19. Lemmas convex on the back or subcari- 

 nate, acute or awn- tipped (obtusish in 

 F. obtusa) 4. Festuca 



Tribe 3. Horueae. — Barley Tribe 

 1. Spikelets solitary at each joint of the rachis. 



2. Spikelets placed edgewise to the rachis; first glume of the lateral spike- 

 lets absent 26. Lolium 



2. Spikelets placed flatwise to the rachis; glumes 2. 



3. Spikelets cylindrical, awned, sunk in the thickened rachis ....21. Aegilops 

 3. Spikelets compressed. 



4. Glumes 1-nerved; spikelets with 2 perfect flowers 22. Secale 



4. Glumes 3- to several-nerved. 



