GRAMINACEAE (GRASS FAMILY) 



68 a Plants cultivated South, sometimes North, for the sugary 



stem or broom-like panicles, sometimes in greenhouses 69 

 b Plants not cultivated for the sugary stem or broom- 

 like panicle 70 



69 a Spikelets not with long silky hairs ; cultivated North 



and South 56. Sorghum, p 122 



b Spikelets with long, silky hairs; cultivated only South 



and in greenhouses 57. Saccharum. p 122 



70 a Spikelets fuzzy with long silky hairs; coarse grass 



46. Phragmites. p 120 

 b Spikelets not as in a 71 



71 a Spikelets boat-shaped, hairy, usually overlapping and 



closely appressed on slender, stiffly spreading, raceme- 

 like branches 47. Homalocenchrus. p 120 



b Spikelets not completely as in a 72 



72 a Spikelets in i-sided racemes arranged in dense panicles; 



coarse grass 22. Echinochloa. p 119 



b Spikelets not arranged completely as in a 73 



73 a Panicle with few stiff branches; spikelets crowded often 



in i-sided clusters at ends of branches 39. Dactylis. p 120 

 b Panicles not completely as in a 74 



74 a Spikelets usually 3-3O-flowered, comparatively large. ... 75 

 b Spikelets i-2-flowered, comparatively small 78 



75 a Spikelets usually 8-3o-flowered, much flattened; leaves 



infolded 48. Eragrostis, p 120 



b Spikelets 3-io-flowered; leaves usually flat 76 



76 a Spikelets blunt at apex, flattened ; flowers somewhat 



spreading 49. Panicularia. p 121 



b Spikelets tapering to apex 77 



77 a Spikelets 5-io-flowered, no tuft of hairs at base of inner 



scale 36. Festuca. p 120 



b Spikelets 2-6-flowered, a tuft of small hairs at base of 



inner scale 55. Poa. p 122 



78 a A conspicuous tuft of hairs as long as the scale at base 



of inner scale of spikelet; panicle densely flowered 



40. Calamagrostis. p 120 

 b No conspicuous tuft of hairs as in a 79 



79 a Cultivated grain ; spikelets 2-flowered, pendulous 



33. A vena, p 120 

 b Not cultivated grains 80 



80 a Spikelets boat-shaped, outer scale about as long as spike- 



let, shining, yellowish-brown or purple; panicle 2-4 



in. long ; aromatic grass 50. Savastana, p 121 



b Plants not completely as in a 81 



117 



