XXIV GRASSES OF BRITAIN, 



LAGURUS. — Floret with a bristly awn. Leaves broad and 

 downy. One species, L. ovatus. 



MILIUM. — Leaves broad. Ligules prominent. Glumes three- 

 ribbed. One species, 31. effusum. 



ARUNDO. — Leaves broad. Ligules wanting. Outer palea 

 acute. Inner palea very short. One species, A. Phragmites. 



SESLERIA. — Glumes about equal, without lateral ribs. Upper- 

 most leaf very short. One species, S. ccerulea. 



ANTHOXANTHUM.— Large glume three-ribbed. Ligules 

 long and pointed. One species, A. odoratum. 



POA. — Glumes three-ribbed. Florets generally webbed. Outer 

 palea three or five- ribbed, the dorsal and marginal ribs mostly hairy ; — 

 or Glumes without lateral ribs. Outer palea three, five, or seven-rib- 

 bed; (when three-ribbed the lowermost floret is much longer than the 

 glumes, with the dorsal rib minutely toothed its whole length.) 

 Twenty-two species, P. pratensis, P. trivialis, P. bulbosa, P. com- 

 pressa, P. subcompressa^ P. polynoda, P. Parnellii, P. nemoralis, 

 P. montana, P. alpina, P. laxa, P. ccesia, P. atinua, P. distans, P. 

 maritima^ P. Borreri, P. procumbenSy P. rigida, P. loliacea^ P. aqua- 

 tica, P. Jluitans, P. sylvatica. 



HIEROCHLOA. — Glumes broad, nearly equal, without lateral 

 ribs, with not more than three florets, all inclosed within the glumes. 

 Outer palea hairy, five-ribbed. Anthers two in the perfect floret. 

 One species, H. borealis. 



TRIODIA. — Florets inclosed within the glumes. Glumes three- 

 ribbed. Ligules wanting. One species, T. decumbens. 



BRIZA. — Glumes nearly equal, spreading, three-ribbed. Florets 

 from five to eight in each spikelet. Outer palea broad, without la- 

 teral ribs, the back gibbous. Two species, B. minor, B. media. 



