122 P0ACEAE 







1. Brachyelytrum er6ctum (Schreb. ) Beiiuv. Stems 3-9 dm. tall, pubescent at and 

 near the nodes : leaf-sheaths villous, especially at the throat ; blades 5-13 cm. long, 6-18 

 mm. wide, rough : panicle 5-15 cm. long, slender, its branches erect or appressed : empty 

 scales of the spikelet unequal, the upper one less than as long as the flowering scale, the 

 lower minute or wanting, the flowering scale, exclusive of the awn, 9-12 mm. long, rough, 

 the awn erect, 2-2.5 cm. long. [Z?. aristatum R. & S.] 



In moist places or woods, Newfoundland and Ontario to Minnesota, Georgia and Kansas. Summer. 



57. FHLEUM L. 



Annual or perennial grasses, with flat leaf -blades and terminal, often long-pedunculate, 

 dense spike-like panicles, which are from elongated, narrow and cylindric, to short, oblong 

 or nearly ovoid. Spikelets crowded, 1-flowered, compressed. Scales 3, the 2 outer empty, 

 persistent, membranous, compressed-keeled, obliquely truncate at the summit, awned, the 

 third scale much shorter, hyaline, truncate and denticulate at the apex, enclosing a nar- 

 rower palet of similar texture and a perfect flower. Stamens 3. Styles distinct, rather 

 long. Stigmas plumose. 



1. Phleum prat^nse L. Stems 3-12 dm. tall, erect, simple : leaf-blades 7-23 cm. 

 long, 4-6 mm. wide, smooth or rough : spike usually elongated, cylindric, 3-18 cm. long, 

 5-8 mm. in diameter : empty scales of the spikelet, exclusive of the awn, 2.5 mm. long, 

 ciliate on the keel, the awn less than % their length. 



In fields and meadows nearly throughout North America. Widely cultivated. Also in Europe 

 and Asia. Summer. TIMOTHY. 



58. ALOPECURUS L. 



Annual or perennial grasses, erect, or decumbent at the base, with flat and lax or 

 rather rigid or convolute leaf-blades, and dense terminal spike-like cylindric panicles. 

 Spikelets articulated below the empty scales, readily deciduous, 1-flowered, compressed, 

 crowded. Scales 3, the 2 outer empty, acute, sometimes short -awned, usually more or less 

 united at the base, compressed-keeled, the keel ciliolate or somewhat winged, the third 

 scale broad, hyaline, obtuse, bearing a short awn or point on the back, the margins some- 

 times united into a short tube at the base, enclosing a perfect flower and sometimes also a 

 hyaline keeled palet. Stamens 3. Styles distinct, or rarely more or less united at the 

 base. Stigmas elongated, somewhat plumose with short hairs. FOXTAIL. 



Empty scales of the spikelet united for % their length, glabrous to hispid on the 



keel. 1. .-1. agrestis. 



Empty scales of the spikelet united for % their length or less, long-ciliate on the 



keel. 2. A. gcniculatus. 



1. Alopecurus agrestis L. Stems 3-6 dm. tall, erect, simple : leaf-blades 4-18 cm. 

 long, 2-6 mm. wide, rough, especially above : spike 4-10 cm. long, 4-8 mm. in diameter : 

 empty scales of the spikelet narroAvly winged, 4-5 mm. long, the flowering scale equalling 

 or slightly exceeding the empty ones, smooth and glabrous, the awn inserted near the 

 base and about twice its length, bent. 



In waste places and on ballast, southern New York, New Jersey, and Mississippi. Summer. 



2. Alopecurus geniculatus L. Stems 1.5-4.5 dm. tall, erect, or sometimes decumbent 

 at the base : leaf-blades 2-15 cm. long, 1-4 mm. wide, rough, especially above : spike 2-8 

 cm. long, 4-8 mm. in diameter : empty scales of the spikelet 2-2.5 mm. long, obtuse or 

 subacute, glabrous, excepting the lateral nerves and strongly ciliate keel, the flowering 

 scale somewhat shorter, obtuse, the awn inserted at or below the middle, equalling or ex- 

 ceeding it. 



In wet soil, Newfoundland to British Columbia, Florida, Tennessee, Arizona, and California. 

 Also in Europe and Asia. Summer and fall. 



59. SPOROBOLUS K. Br. 



Perennial or rarely annual grasses, varying much in habit, with flat or convolute leaf- 

 blades and terminal panicles, which are contracted, sometimes cylindric and spike-like, 

 often elongated, or open and diffuse. Spikelets small, sometimes minute, 1-flowered, or 

 very rarely 2-4-flowered. Scales 3, rarely 46, membranous, acute or obtuse, rarely awn- 

 pointed or short-awned, the 2 outer empty, the first shorter than the second, the remaining 

 scale or scales longer or about equalling the second scale, enclosing a perfect flower, and a 

 2-nerved, often deeply 2-cleft or 2-parted, palet which is equal in length to, or a little 

 shorter than, the scale, rarely awned and exceeding it. Stamens 2 or 3. Styles short, 

 distinct. Stigmas plumose. RUSH GRASS. 



