136 THE TRUE GRASSES. 



e. Flowering glumes with five sharp, subulate divi- 

 sions, which are bent backwards. Spikelets two- 

 flowered ; inflorescence capitate. . 206. Echinaria. 



f. Flowering glumes with 3-5 lanceolate, pointed, 

 rigid, and erect or straight lobes. Spikelets many- 

 flowered, in racemes 207. Orcuttia. 



g. Flowering glumes with five delicate awns. 



210. Sesleria, Sec. Psilatliera. 

 h. Flowering glumes five-cleft, divisions awl-shaped, 

 the middle and two outer ones awned. 



199. Calamochloa. 

 Note. — Compare Triruphis. 



i. Flowering glumes deeply 3-4-cleft-with a dorsal 



awn 201. Pommoreulla. 



k. Flowering glumes deeply four-cleft, usually awned 



between the hyaline divisions. 200. Cathestechum. 

 1. Flowering glumes of the fertile flower three-cleft, 



three- awned. 



a. Plant dioecious, the two sexes very unlike. 



202. Scleropogon. 



/?. Plant hermaphrodite. . . . 203. Triraphis. 

 B. Flowering glumes entire or two-tootlied to two-cleft, awn- 

 less or tvith one awn (3-5-aivned only in a variety of 

 Bromus macrostachys). 



a. Rachilla or flowering glume (at least of the fertile 

 flower) with long hairs which envelop the latter. 

 Tall, reed-like grasses. 



a. Plant dioecious, ? spikelets hairy, $ spikelets 



naked 214. Gynerium. 



(3. Plant hermaphrodite (very rarely dioecious), all 



the spikelets hairy. 



I. Flowering glumes thick-membranaceous, 



five-nerved. . . . 215. Ampelodesmos. 



II. Flowering glumes thin-mem branaceous or 



hyaline, three-nerved. 



1°. Flowering glumes hairy, rachilla naked. 



216. Arundo. 

 2°. Hairs on the rachilla only. 



217. Phragmites. 



b. Rachilla and flowering glume naked or hairy ; 

 hairs much shorter than the glumes. 



I 



