5-AG GRAMINE.E. (GRASS FAMLLY.) 



* * Glumes distinct, concave or keeled. Palere membranaceous. Grain free. Spikelets in 



open or contracted panicles- 



5. SPOROBOLCS. Flowers awnless. Seed loose in the globose or obovoid pericarp. 



6. VILFA. Flowers awuless. Seed adhering to the closely investing pericarp. 



7. AGROSTIB. Pales shorter than the nearly equal glumes, the lower uwued on the back, 



the upper sometimes wanting. 



8. POLYPOGON. Palere much shorter than the long-awned glumes, the lower one truncated 



and toothed. Stamens 3. Panicle spike-like. 

 T». CI XX A. Palere rather longer than the acute glumes, the lower one awned under the apex. 

 Stamen 1. Panicle loose. 



10. MIIII.EXBERGIA. Lower glume smaller than the upper one. Palere bearded at the 



base, the lower one mueronate or awn pointed. Stamens 3- 



11. BRACIIYELVTRUM. Lower glume obsolete. Lower palea lODg-awned. A pedicel of a 



second flower at the back of the upper palere. Stamens 2. 



12. CALAMAGROSTIS. Palese surrounded with a tuft of long hairs, the lower awned on the 



back. 



* * » Palere raised on a hairy stalk ; the lower one awned, indurated, and involute, closely 



investing the grain. 



13. STIPA. Lower palea with a single contorted awn jointed with its apex Panicle short. 



14. STREPTACHNE. Lower palea with a single straight or curved awn continuous with its 



apex. Panicle elongated. 



15. ARISTIDA. Lower palea triple-awncd. Panicle elongated. 



Tribe TIT. CHLORIDES. — Spikelets 2 -several-flowered (in No. 16 one-flowered), in 

 1-sided spikes. Rachis jointless. Upper flowers imperfect. Glumes and palere 2. Spikes 

 racemed or digitate, rarely single. 



* Spikelets strictly 1-flowered. (See Paspalum.) 

 10. SPARTTNA. Spikelets flat, imbricated in alternate spikes. 



» * Spikelets 2 - 3-flowered, only the lowest flower perfect. 

 17. GVMNdl'OGOX. Spikelets linear, scattered. Lower palea and rudiment awned. Spikes 



racemed. 

 1^. ETJSTACBTYS. Spikelets roundish, crowded. Lower palea mueronate. Spikes digitate. 



19. CYXOIiOX. Lower palea awuless. Culms creeping. Spikes digitate. 



• * * Spikelets 4 -• 5-flowered, one of the middle ones only perfect. 



20. CTEX1UM. Lower palea stout-awned on the back. Spike solitary. 



» » * ■» Spikelets mostly several-flowered, the lower flowers perfect. 



21. DACTYLOCTEXICM. Spikes digitate. Upper glume awned. Palere pointed. 



22. ELEUSINE. Spikes digitate. Glumes and palea- awuless. 



23. LEPTOCHLOA. Spikes racemed, long and slender. Glumes awnless. 



Tkiiie IV. FESTDCACEJF,.- Spikelets panicleil, few -many -flowered j the upper ami 



(in No. 86 and 87) the lower flowers also imperfect. Glumes 2. Palea 2, membranaoeou 



or rarely indurated, awnless, or the lower one with a straight awn at or near the apex. 

 Stamens 1-3. 



• Grain smooth, free from tin- palese. Lower flowers perfect. 

 4- Lower palea .'! -6-tOOthfid or :i«iinl. 



21. TRIC08PI8. Bpikeleta 5-7 flowered. Lower palea slightly 2-cleft, tin- 8 halrj uerrea 

 percurrent. 



20. TRTPLA8I8. BpOteletl •'! -flowered, the lower palea deeply 2 cleft, and with a plumose 

 awn between the teeth. 



