4 s 



THE TRIBES AND THEIR GENERA. 



Holcus. Inflorescence a panicle. Spikelets falling entire. 

 Florets two, upper floret male, awned ; lower floret perfect, 

 awnless. Glumes erect, beardless, ovate, compressed, keeled, 



enclosing florets, one of which is 

 stalked. Outer palea pointed, that 

 of male floret with a dorsal awn. 

 Inner palea smaller, awnless, apex 

 entire. Lodicules single, bifid, 

 membranous. Stamens three. Ovary 

 ovate. Style short or absent. Stig- 

 mas oblong and feathery, protrud- 

 ing above the base or middle of 

 the floret. Grain ovate, attached to 

 the indurated paleae. Broader leaves 

 twisted to the left. 



Holcus lanalus. 

 Floret. For Spikelet see p. 103. 



Species. 



H. lanalus, 45. 

 77". -mollis, 46. 



Aira. Panicles loose. Spikelets small. Florets two, nearly 

 sessile. Glumes equal, ovate-lanceolate, acute, thin, mem- 

 branous, persistent. Outer palea like glumes in height and 

 texture, bifid at apex, rounded on back, awn dorsal and short. 

 Inner palea two-nerved. Stamens 

 three ; filaments long and capil- 

 lary; anthers oblong, forked at 

 each end. Ovary glabrous. Styles 

 bristle shaped, spreading. Stigmas 

 feathery, protruding above the 

 base or middle of the spikelet. 



Species. A. ccsspitosa, 36. 



A. flexuosa, 37. 



A. canescens, 38. 



A . praecox, 39. Mm wyophyiiea. 



Floret. For Spikelet see p. 72. 

 A . caryophyllea, 40. 



