14 GRAMINEAE 



b. Flowers various, the upper perfect, the lower staminate and with the 

 scale strong-ly awned. 38. Arrhenatherum. 



B. Flowering scales awned between their usually awned teeth. 



39. Danthonia. 

 Tribe IX. CHI^ORIDEAE. 

 Spikelets deciduous as a whole. 41. Spartina. 



Spikelets with at least the empty scales persistent. 

 Spikelets with one perfect flower. 

 Spikes few, long and slender, digitate. 40. Capeiola. 



Spikes many, short and stout, racemose. 42. Atheropogon. 



Spikelets with 2-3 perfect flowers. 

 Spikes with terminal spikelets. 43. Eleusine. 



Spikes with the rachis extending beyond the spikelets in a manifest tip. 



44. Dactyloctenium. 

 Tribe X. FESTUCEAE. 

 Hairs on the rachilla or flowering scale very long and enclosing the latter : tall 



reed-like grasses. 45. Phragmites. 



Hairs, if any, on the rachilla or flowering scales shorter than the scale ; grasses 

 of lower stature. 

 Flowering scale 1-3-nerved, or rarely with faint additional intermediate nerves. 

 Lateral nerves of the flowering scale pilose. 

 Internodes of the rachilla long, the deeply 2-lobed flowering scales at- 

 tached by a long pointed callus. 47. Triplasis. 

 Internodes of the rachilla and the blunt callus of the flowering scale 

 short. 46. Tridens. 

 Lateral nerves of the flowering scale glabrous. 

 Second empty scale similar to the first. 



Rachilla of the spikelet continuous : palets often persistent. 



48. Eragrostis. 

 Rachilla of the spikelet articulated. 50. Koeleria. 



Second empty scale very dissimilar to the first, broad and rounded at the 

 summit. 49. Eatonia. 



Flowering scales 5-many-nerved. 

 Spikelets with two or more of the upper scales empty, broad and enfolding 



each other. 51. Melica. 



Spikelets with the upper scales flower-bearing, or smaller and empty. 

 Empty basal scales 3-6. 52. Uniola. 



Empty basal scales 2. 

 Spikelets borne in fascicles which are arranged in a glomerate or inter- 

 rupted panicle. 54. Dactylis. 

 Spikelets borne in panicles or racemes but not in fascicles. 

 Spikelets relatively large, cordate. 53. Briza. 

 Spikelets relatively small, not cordate. 

 A. Stigmas inserted at or near the apex of the ovary. 

 Flowering scales with the nerves parallel. 

 Styles present : flowering scales markedly s-7-nerved. 



56. Panicularia. 

 Styles wanting : flowering scales obscurely 5-nerved. 



57. PUCCINELLIA. 



Flowering scales with the lateral nerves converging above toward 

 the midnerve. 

 a. Flowering scales strongly keeled on the back, pubescent 

 on some or all of the nerves : hilum punctiform. 



55. POA. 



