GRAMINE^. (grass FAMILY.) 647 



10. S. airoldes, Torr. Culm tufted, often stout, erect, |-3° higli, 

 leaves strongly revolute and attenuate, rather rigid ; panicle open and diffuse, 

 broadly pyramidal, glabrous; spikelets solitary on slender pedicels, 1" long; 

 lower glumes unequal, rather obtuse. — Neb. to Tex., and westward. 



S. asperif6lius, Thurb., a similar but smaller species, with thinner and 

 shorter leaves very rough on the margin, the inflorescence scabrous, and spike- 

 lets smaller, with the glumes nearly equal, is very common westward, and prob- 

 ably occurs within our limits — as also S. coxfuscs, Vasey (8. ramulosus of 

 authors, not Kunth), a low slender annual, with very short culms and a deli- 

 cate diffuse panicle, the very small spikelets {^" long) on filiform-clavate 

 pedicels. 



* * * Empty glumes almost equal ; panicle racemose-elongated , open, the pedi- 

 cels capillari) ; sheaths naked at the throat ; spikelets not unfrequently two- 

 Jlowered ; perennial. 



11. S. COmpressus, Kunth. Very smooth, leafi/ to the top ; culms tufted, 

 stout, verij Jiat ; sheaths flattened, much longer than the internodes ; leaves 

 erect, narrow, conduplicate-channelled ; empty glumes acutish, about one third 

 shorter than the obtuse flowering one. — Bogs, on Long Island and in the 

 pine-barrens of N. J. Sept. — Forming strong tussocks, 1-2° high. Panicle 

 8-12' long ; spikelets V long, purplish. 



12. S. serotinus, Gray. Smooth; culms very slender, flattish (8-15' 

 \ag\\), few-leaved ; leaves very slender, channelled; panicle soon much exserted, 

 the diffuse capillary branches scattered ; glumes ovate, obtuse, about half the 

 length of the flower. — Sandy wet places, Maine to N. J. and Mich. Sept, — 

 A very delicate grass ; the spikelets half a line long. 



29. AGROSTIS, L. Bent-Grass. (PI. 7.) 



Spikelets 1 -flowered, in an open panicle. Empty glumes somewhat equal, 

 or the lower rather longer, usually longer than the flowering one, pointless. 

 Flowering glume and palet very thin, pointless, naked ; the first 3 - 5-nerved, 

 frequently awned on the back ; the palet often minute or none. Stamens 

 chiefly 3. Grain (caryopsis) free. — Culms usually tufted, slender ; root com- 

 monly perennial. (Name from aypos, afield, the place of growth.) 



§ 1. AGROSTIS proper. Palet manifest, hut shorter than the glume. 



A. Alba, L. (Fiorin or White Bent-Grass.) Eootstocks creeping 

 or stoloniferous ; culms 1-2° high, often decumbent at base; leaves short, 

 flat, the ligule long and acute ; panicle contracted after flowering, greenishj 

 purplish or brownish, the branches slightly rough ; flowering glume nearly 

 equalling the empty ones, 3-nerved, rarely short-awned, the palet about half as 

 long, — Meadows and fields, a valuable grass ; naturalized from Eu. and cul- 

 tivated, and perhaps native north and westward. 



Var. VULGARIS, Thurb. (Red Top. Herd's-Grass of Penn., etc.) (PI. 7, 

 fig. 1, 2.) Panicle more or less spreading after flowering; ligule short and 

 truncate. (A. vulgaris, With.) — Low meadows and pastures; nat. from Eu. 

 and cultivated, also perhaps indigenous. 



1. A. arachnoides, Ell. Culms (1° high) and leaves very slender; 

 panicle open, weak and drooping; glumes nearly equal, ronghish on the keel 

 and margins, the flowering glume shorter, with 2 minute bristles at the trun- 

 cate apex and a long exceedingly delicate a^vn on the back above the middle , 

 palet minute. — Mo. to Ky., Tenn., and S. Car. 



