KEY TO COMMON GRASSES. 45 



on the left of the page and consider the two alternatives. 

 No rhizomes takes us to 19. Here no colouration takes us 

 to 22. At 22 no yellow colouring takes us to 23. Here no 

 sweUings at the base leads us to 25. Leaf sheath is com- 

 pressed so go to 26. Not a "Poa" blade so go to 27, where the 

 total absence of hairs finally identifies the grass as Cocksfoot. 



1. Hairy on leaf, or sheath, or both, or only round ligule 2 

 Hairless 14 



2. Hairs at least as conspicuous on leaf as on sheath, 



or chiefly near ligule 3 



Hairs long and numerous on sheath ; much less con- 

 spicuous on blade Prairie Grass 



3. Hairs long and silky round hgule, shorter or absent 



elsewhere 4 



Hairs not chiefly round ligule 7 



4. Ligule very small if present at all (see note) 5 

 Ligule quite obvious, withhairs in front of or behind it. 6 



5. Thick ring or tuft of hairs round mouth of blade. 



Blade rather narrow, sometimes hairy. No 

 clasping ears Danthonla 



Thin ring of hairs ; blade broad and Ught green ; 

 distinct though not large clasping ears Microloena 

 (see note) 



6. Very large ligule ; hairs long and silky behind it ; 



strong rhizomes ; often a few scattered silky hairs 

 on edges of sheathing parts of leaves Paspalum 

 Moderate Ugule ; hairs round mouth of blade ; 

 often hairy elsewhere ; no rhizomes ; taste 

 suggesting smell of hay. Sweet Vernal 



7. Distinct red and white veins at base of sheath, best 



seen when sheath stripped backwards 8 



Note. — Ratstail and Indian Doab both fall here, as well as 

 Microloena and Danthonla. See detailed descriptions on pp. 39-40. 



