. (GKASS FAMILY.) 645 



P. PRATENSE, L. (TIMOTHY. HERD'S-GRASS in New Eng. and N. Y.) 

 Tall ; spike Img-cylindrical ; lower glumes ciliate on the back, tipped with a 

 short bristle. Meadows, commonly cultivated for hay. (Nat. from Eu.) 



1. P. alpinum, L. Low; spilce ovate-oblong; lower glumes strongly 

 ciliate on the back, tipped with a rough awn about their own length. Alpine 

 tops of the White Mountains, N. H., and high northward. (Eu.) 



27. AL OPE GURUS, L. FOXTAIL GRASS. (PI. 7.) 



Spikelets 1 -flowered, jointed on the pedicel. Lower glumes boat-shaped, 

 stronglv compressed and keeled, nearly equal, united at base, equalling or ex- 

 ceeding the flowering glume, which is awned ou the back below the middle ; 

 palet mostly wanting ! Stamens 3. Styles mostly united. Stigmas long and 

 feathered. Clusters contracted into a cylindrical and soft dense spike ; peren- 

 nial. (Name from dAccir7j|,/o.r, and oupd, tail, from the shape of the spike.) 



A. PRATENSIS, L. (MEADOW FOXTAIL.) Culm upright, smooth (2 high) ; 

 the upper leaf much shorter than its inflated sheath ; spike stout, H - 2' long ; 

 flo we ring glume equalling the acute lower glumes ; aim erscrted in<>r<- than half 

 its length, twisted. Meadows and pastures, eastward. May. (Nat. from Eu.) 



A. GENiccrA-rus, L. (FLOATING F.) (PI. 7, fig. 1-4.) Culm ascending, 



often bent at the lower joints ; upper leaf as long as its sheath ; spike slender, 



1-2' long ; flowering glume rather shorter than the obtuse lower glumes, the aicn 



from near its base and projecting from half to twice its length beyond it. Moist 



meadows, eastward. June -Aug. (Nat. from Eu.) 



Var. aristulatus, Torr. The awn very slender and scarcely exserted. 

 (A. aristulatus, Michx.) In water and wet places; common. June- Aug. 



28. SPORO BOLUS, R. Br. DROP-SEED GRASS. RUSH-GRASS. 



(PI. 7.) 



Spikelets small, 1- (rarely 2-) flowered, in an open or contracted or spiked 

 panicle. Lower glumes persistent, 1 - 3-nerved, not awued or pointed, the 

 lower smaller; flowering glume of the same texture as the lower ones 

 (membrauaceo-chartaceous) and usually longer than they, naked, awuless and 

 mostly pointless, 1-nerved (rarely somewhat 3-uerved) ; palet similar, 2-nerved. 

 Stamens chiefly 3. Stigmas simply feathery. Grain globular to oblong or 

 cylindrical, deciduous, often very thin, containing the loose seed. Culms 

 wiry or rigid. Leaves involute, the throat usually bearded, and sheaths often 

 enclosing the panicles. (Name from o-iropn, seed, and /3d\\u, to cast forth.) 

 * Panicle contracted, often simple ; grain oval or oblong ; perennial, except n. 2. 



1. S. asper, Kunth. Culms tufted (2-4 high); lowest leaves very 

 long, rigid, rough on the edges, tapering to a long involute and thread-like 

 point, the upper short, involute ; sheaths partly or at first wholly enclosing 

 the contracted panicle; flower much longer than the unequal lower glumes; 

 grain oval or oblong. (Vilfa aspera, Beauv.) Sandy fields and dry hills, 

 especially southward. Sept. Spikelets 2-3" long. Flowering glume and 

 palet rough above, smooth or hairy below, the palet tapering upward, acute, 

 and one half to twice longer than the glume, or else obtuse and equalled or 

 even considerably exceeded by the glume ! 



2. S. vaginsefldrus, Vasey. (PI. 7, fig. 4, 5.) Culms slender (6-12' 

 high), ascending; leaves involute-awl-shaped (1-4' long); panicles simple 

 and spiked, the lateral and often the terminal concealed in the sheaths ; flower- 



