XXll GRASSES OF BRITAIN. 



GENERA. 

 ECHINOCHLOA. — Spikelets with an involucre of smooth bris- 

 tles. Large glume hairy. Neutral floret of two paleae, the outer 

 palea awned. One species, E. Crus-galli. 



SETARIA. — Spikelets with an involucre of rough bristles. 

 Glumes not hairy. Neutral floret of one palea, not awned. Two 

 species, S. viridis, S. verticillata. 



DIGIT ARIA. — Spikelets in pairs with distinct footstalks arranged 

 on one side of a flattened rachis. Ligules prominent, entire. Styles 

 long, distinct. Stigmas short. Anthers cloven at each end. Two 

 species, D. sanguinalis, D. humifusa. 



CYNODON. — Spikelets single, with short footstalks arranged 

 on one side of the rachis. Glumes nearly equal. Ligules want- 

 ing. Floret rather longer than the glumes. Styles distinct, pro- 

 minent. One species, C. dactylon. 



KNAPPIA. — Spikelets single, with short footstalks arranged on 

 one side of the rachis. Glumes equal. Ligules prominent. Floret of 

 one palea, shorter than the glumes. Styles very short. Stigmas 

 slender and very long. Anthers cloven at each end. One species, 

 K. agrostidea. 



SPARTINA. — Spikelets sessile, arranged on one side of the ra- 

 chis. Glumes very unequal. Ligules very short. Styles long, partly 

 united. Anthers cloven below, entire above. Two species, S. 

 stricta^ S. alterniflora. 



ALOPECURUS. — Glumes not awned. Floret of only one palea, 

 with a long awn arising from below the centre. Six species, A. 

 agrestisj A. pratensis, A. alpinus^ A. geniculatus^ A. fulvus^ A. bul- 



PHLEUM. — Floret of two palese not awned, the outer palea oc- 



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