584 POACE^. 



C. Bovine Hack. Lignle very short, truncate, throat of 

 sheath often falcate-auriculate, blades usually all flat, 

 rarely subconvolute. Ovary obovoid, glabrous. Grain 

 often adherent to glume andj^alea. 



a. Arctic grasses, small 5 



a. Not arctic, larger (b) 



b. Upper ligule 1-2-5 mm. long, floral glume 6-8 



mm. long 6 



b. Upper ligule 1 mm. long, or less (c) 



c. Floral glume 4 mm. long, coriaceous, obscurely 



nerved 7 



c. Floral glume 5 mm. long, chartaceous, ob- 

 scurely nerved 8 



c. Floral glume 5-9 mm. long, not coriaceous. . (d) 

 d. Floral glume 6-8 mm. long, scabrid, awn 8- 



12 mm. long 9 



d. Floral glume 8-9 mm. long, scabrous, short 



awned 10 



d. Floral glume 7-8 mm. long, scabrous, short 



awned 11 



d. Floral glume 6 mm. long, scabrous, short 



awned 12 



d. Floral gliime 6-7 mm. long, scabrid toward 



the apex, rarely awned 13, 14 



d. Floral glume 5-7 mm. long, awn 5-12 mm. 



long 15 



D. OviN^ Hack. Ligtile very short, truncate, usually hi- 

 aurictdate, blades all conduplicate or those of the culm 

 inore or less fattened. Ovary obovate-oblong, glabrous, or 

 the apex rarely thinly hispid. Grain adhering closely to 



fl,or(d rjlume and palea (e) 



e. Ligule very short, symmetrically biaurieulate, lilades 

 more than 2 cm. long, all conduplicate, in transverse 

 section, oval to oblong or cuueate, oblong. Ovary 



very smooth (m^ 



m. Leaves of culm 2-3 16 



