53 



Group VI. Net-sheathed Grasses. (Fig. 14.) 

 Sheath flat, and blade folded in bud ; aquatics ; blade 

 blunt pointed. Catabrosa. Glyceria. 

 Catabrosa aquatica, Beauv. (Water whorl grass). 



Ligule rounded ; blade like Poa. 

 Fig. I. Rounded apex of blade. 

 Fig. 2. Rounded base of blade and ligule. 

 Fig. 3. Transverse section shewing the air cavities in 



the folded blade (magnified). After Lund. 

 Fig. 4. Transverse section of mature blade ribless, 

 and with median lines like Poa (magnified \. 

 After Lund. 

 j Glyceria fluitans, M. 



&K. 

 (Floating sweet grass): 



Base of blade With a yellow triangular 

 spot on each side . . . 



Sheath ! With a prominent keel 



and a rounded edge 



Ribs ; Acute on upper and lower 



Glyceria aquatica, 



Sm, 

 (Reed sweet grass). 



With a brown triangu- 

 lar spot on each side. 

 With two acute edges. 



Absent. 



surface of blade 

 /Fig. 5. Apex of blades. 

 Fig. 6. The hooded apex flattened and split. 

 Fig. 7. Base of blade and ligule. 

 Fig. 8. Section of sheath (magnified). Observe keel 



rounded edge, and ribs. After Lund. 

 Fig. 9. Transverse section of blade (magnified). 

 Observe the acute ribs on upper and 

 lower surface. After Lund. 

 Fig. 10. Apex of blade. 

 Fig. ii. Base of blade and ligule. 

 Fig. 12. Section of sheath. Observe the acute edges. 

 Fig. 13. Part of blade (magnified). Observe the air 



cavities in the cut end. After Lund. 

 Fig. 14. The ligule with an actite point, and the netted 



sheath spread out. After Lund. 

 Sheath round, and blade rolled in bud ; apex of blade 

 acute. 

 Phalaris arundinacea, L. (Reed canary grass). Often 



confounded with cocksfoot. 



Fig. 15. Apex of blade. Fig. 16. Base of blade. 

 Fig. 1 7. Section of shoot. Observe the rolled blade. 

 Hierochloa borealis, R. & S. (Northern holy grass). 

 Bitter tasted, like sweet vernal. Blade thin, flaccid, 

 and taper based. Very rare. 



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