430 GRAMlNACEJi. 



C. arundinacea Willd. : culm simple, smooth ; leaves linear-lanceolate ; 

 panicle large, loose, with the branches somewhat in fours, capillary. 

 Muhlenbergia Cinna Trin. Agrostis Cinna Pursh. 



Wet grounds. Can. to Car. Aug. ^.Culm 25 feet high. Leaves a 

 foot or more in length, rough on the margin. Panicle terminal, 8 12 inches 

 long. Flowers green or purplish. Reed-like Cinna. 



19. AGROSTIS. Linn. Bent Grass. 



(From the Greek aypos, afield ; in reference to the place of growth.) 

 Glumes 2, nearly equal, usually longer than the flower, point- 

 less. Paleae 2 ; the lower one mostly awned on the back ; upper 

 often minute or nearly wanting. Panicle diffuse. 



1. A. stricta Willd.: culm erect; panicle elongated; the branches ver- 

 ticillate, nearly erect ; glumes equal, oblong acute ; palese two, smaller 

 than the glumes, unequal ; the lower one twice as long as the upper, with 

 an awn at the base about twice as long as the palea. 



Sandy fields. N. Eng. and N. Y. June. 1\.. Culm about a foot high, 

 smooth, with black nodes. Leaves linear-lanceolate, rough on the margin. 

 Panide oblong, the primary branches whorled in fives. Spikelels somewhat 

 crowded. Upright-flowered Bent-grass. 



2. A. vulgaris With,: culm ascending; panicle oblong, spreading, the 

 branches smoothish and at length divaricate ; paleae unequal, the outer 

 one 3-nerved. A. alba Muhl. A. polymorpha Gray. 



Pastures and meadows. Throughout the U. S. July. 1\.. Root creeping, 

 throwing out many mostly ascending culms 1 2 feet high. Leaves linear- 

 lanceolate, flat, scabrous, the ligule very short. Panicle 4 6 inches long, pur- 

 plish, the branches a little rough. Introduced, but now completely naturalized. 



Herd's- grass. Red-lop. 



3. A. alba Linn.: panicle contracted, at length spreading, the branches 

 hispid ; lower palea 5-nerved ; ligule oblong. A. stolonifera Linn. A. de- 

 cumbens Muhl. 



Wet meadows. Throughout the U. S. June, July. %.. Root creeping. 

 Culm 1 2 feet high, ascending, often rooting at the lower joints. Leaves 

 roughish, the sheaths smooth. Panicle pale green or purplish. Closely allied 

 to the preceding, but generally stouter and taller. Introduced, but everywhere 

 naturalized. Herd's-grass. Fiorin-grass. 



4. A. later ijlora Mich. : culm erect, branched ; panicles lateral and termi- 

 nal, contracted, dense-flowered ; glumes acuminate ; paleae about as long 

 as the glumes, equal, pubescent at base, awnless. A. Mexicana MuM. 

 Muhlenbergia Mexicana Trin. 



Moist grounds. N. Y. to Virg. Aug., Sept. 1\.. Root creeping. Culm 

 2 feet or more high, much branched, often geniculate. Leaves broad-linear, 

 flat. Panicles numerous, terminating the branches, pale green or purplish. 



Lateral-jlowered Bent-grass. 



5. A. sobolifera Muhl.: culm erect, branched; panicle contracted, fili- 

 form, simple, with appressed alternate branches ; palese equal, longer than 

 the glumes, awnless, hairy at base, the lower one mucronate at the tip. 

 Muhlenbergia soboLifera Trin. 



Rocky woods. N. Y. to Virg. Aug., Sept. %. Culm 2 feet high, sobolif- 

 *>us, sometimes decumbent. Leaves pale green, somewhat scabrous. Pan- 

 icle with Ihe flowers rather crowded. Slender-branched Bent-grass. 



