GRAMINE^E. 



317 



1. Leersia. Spikelets i-flowered, compressed, perfect, in secund 

 racemes, arranged in panicles. Paleae 2, compressed, awnless, nearly 

 equal ; lower broader. Stamens 1-6. Stigmas plumose, y. 



L. ORYZOIDES (Cut-Grass). Culm rough backward, with hooked prickles, 

 as also the lanceolate leaves ; panicle sheathed at base, with numerous diffuse 

 branches ; stamens 3 ; paleae whitish, ciliate on the keel. In wet grounds, 

 1-2 feet high. August. 



2. Phleum. Glumes 2, much longer than the paleae, mucronate 

 or awned. Palece 2, unequal, truncate, included in the glumes. Sta- 

 mens 3. 11 



P. PRATENSE ( Timothy. Herd's Grass}. Culm erect, simple, smooth, 

 sometimes bulbous at base ; leaves flat, glaucous ; flowers in a long, dense, 

 simple, terminal, cylindrical spike ; glumes ciliate on the back, truncate, 

 tipped with a very short awn ; anthers purplish. June- July. 



3. Agrostis. Spikelets i-flowered, paniculate. Glumes 2, sub- 

 equal, or the lower one larger, mostly longer than the paleae. Paleae 

 1-2 ; lower one larger, often awned ; upper one often wanting, or mi- 

 nute. Stamens 3. Caryopsis free. y. 



A. VULGARIS (Red-top. Herd's Grass in Penn.). Culm mostly erect, 

 slender ; leaves linear, with smooth sheaths ; ligule short, truncate ; panicle 

 spreading, with slender, purplish branches ; lower palea 3-veined, twice as 

 long as the upper, equaling the glumes, rarely awned. Culm 1-2 feet high. 

 July. 



4. Muhlenbergia. Spikelets i-flowered, in more or less contract- 

 ed, often spicate panicles. Glumes acute, mucronate, persistent ; lower 

 one smaller, often minute. Paleae 2, usually bearded at base, inclosing 

 the grain. Stamens 3. y. 



M. MEXICANA (Mexican Drop-seed}. Culm erect, ascending, very branch- 

 ing, and very leafy above ; leaves linear, short ; panicles numerous, contract- 

 ed, densely flowered ; branches somewhat spicate ; glumes acute, unequal ; 

 upper glume as long as the very acute, lower palea. In damp grounds, 1-3 

 feet high. August. 



5. Calamagrostis. Spikelets i-flowered, often with a rudiment- 

 ary flower, in a loose panicle. Glumes 2, nearly equal in length, sur- 

 rounded by a tuft of white bristles. Lower palea awned on the back, 

 below the tip, or awnless, mostly longer than the upper one. Sta- 

 mens 3. 



C. CANADENSIS (Blue-joint). Culm simple, tall, stout, rigid ; leaves 

 with smooth sheaths, linear-lanceolate ; panicle oblong, loose ; lower palea 

 3~5-nerved, equaling the tuft of hairs surrounding it, and with a very fine 

 awn on the back below the tip, scarcely exceeding it. A reedy grass, 2-5 

 feet high. July-August. 



