IX] " SEEDS " 159 



much gi'ooved, fusiform, 2 — 3 mm. long, glumes unequal, 

 somewhat keeled and rough. 



(2) Awn dorsal or basal, fine and hair-like, and 

 little or not at all twisted or kneed. "Seed" 

 small. 



* A pencil of silky hairs on base or rachilla. Palea 

 bifid at the tip. 



t Basal hairs longer than palea, and obscuring the 

 avm. 



Galamagrostis Epigeios. 



Of little importance. Digraphis has no awn. 



Galamagrostis Epigeios, Roth. 



Palea about 3 mm. long with toothed apex and very 

 thin caryopsis 1 mm. A conspicuous tuft of fine silky 

 hairs, longer than the palea at the base and on the 

 rachilla. 



Awn slender, dorsal, about as long as the palea. 



C. striata, Nutt. and C. strigosa, Hartm. are rare. 



tt Basal hairs shorter than palea. 



3 Awn brown, bearded in the middle, thickened 

 and white above. 



Aira canescens. 



The student will find considerable difficulties in the various 

 species of Aira and Agrostis, owing to their small size and variability 

 as regards awn and basal hair-tufts. All these are weeds, but some 

 occur as adulterants. 



Aira canescens, L. 



" Seed " (apart from the awn, it is very like Agrostis) 

 1-5 — 2 mm., with a very thin, smooth, keeled, two-nerved 



