GRAMINEAE. 1 09 



ing a rough awn 1-2 mm. long from the 2 -toothed apex. In damp woods, Newf. 

 to Br. Col., south to N. J., in the Alleghanies to N. Car., toWis., and in the Rocky 

 Mts. to Colo, and Utah. Also in Northern Europe. Aug. -Sept. \C. pendula Trin.] 



41. AGROSTIS L. 



Annual or perennial tufted grasses with flat or bristle-like leaves and panicu- 

 late inflorescence. Spikelets I -flowered. Scales 3; the 2 outer empty, membra- 

 nous, keeled, acute; the third shorter, obtuse, hyaline, sometimes bearing a dorsal 

 awn, subtending a perfect flower; palet shorter than the scale, sometimes minute 

 or wanting. Stamens usually 3. Styles distinct, short. Stigmas plumose. Grain 

 free, enclosed in the scale. Seed adherent to the pericarp. [Name Greek, refer- 

 ring to the field habitat of many species.] A genus of about 100 species, widely 

 distributed throughout the world, particularly numerous in temperate regions. 

 Besides the following, some 15 others are found in western N. Am. 



Palet conspicuous, at least one-third as long as the scale. 



Panicle open, its branches long and usually spreading. I. A. alba. 



Panicle dense and contracted, spike-like, its branches short and appressed. 



2. A. coarctata. 

 Palet inconspicuous, minute or wanting. 



Branches of the contracted panicle "short, spikelet-bearing to the base ; third scale 



awnless. 3. A. asperifolia. 



Branches of the panicle slender, naked below, spikelet-bearing from about the middle 



to the end. 

 Third scale awned. 



Awn very finely filiform, barbellate, at least twice the length of the spikelet. 



4. A, Elliottiana. 

 Awn stouter, glabrous, rigid, usually bent, less than twice the length of the 



spikelet. 



Branches of the panicle generally ascending ; spikelets 2 mm. long. 

 Culms 1.5 dm. or less *all ; panicle 2.5 cm. or less long; a tufted 



alpine grass. 5. A. rupestris. 



Culms 3-6 dm. tall ; panicle exceeding 5 cm. long. 



6. A. canina. 

 Branches of the panicle usually spreading; spikelets 2.5-3 mm. long. 



7. A. rubra. 

 Third scale not awned, or very rarely bearing a short awn. 



Culms weak, usually decumbent and often prostrate at base ; leaves lax ; 



spikelets 1.5 mm. long. 8. A. perennans. 



Culms and leaves erect. 



Branches of the panicle capillary, elongated, usually dividing above the 



middle, the spikelets crowded at the extremities. 

 Spikelets 1.5-2 mm. long ; leaves short. 'g. A. hyemalis, 

 Spikelets 2.5-3 mm. long ; leaves elongated. 



10. A. altissima. 

 Branches of the panicle not elongated, dividing at or below the middle. 



Spikelets about 2 mm. long ; a grass of low elevations. 



11. A. intermedia. 

 Spikelets 2.5-3 mm l n g 5 a high-mountain grajs. 



12. A, Novae-Anglian, 



1. Agrostis alba L. RED-TOP. FIORIN. HERD-GRASS. (I. F. f. 362.) 

 Culms 2-7.5 dm- tall, erect or decumbent at the base, often stoloniferous, simple, 

 smooth and glabrous. Leaves 5-20 cm. long, 2-6 mm. wide, scabrous ; panicle 

 5-22.5 cm. in length, usually open, or sometimes contracted after flowering, green 

 or purplish, the branches ascending or erect, the lower 2.5-7.5 cm. long; spikelets 

 2-2.5 mm - l n g; outer scales about equal, acute, smooth and glabrous, except on 

 the hispid or scabrous keel; third scale shorter, obtuse or acute, the palet at least 

 one-third its length. A most variable species, occurring in fields and meadows 

 nearly throughout N. Am., extensively cultivated for fodder. Naturalized from 

 Europe, and perhaps also native northward. July-Sept. 



2. Agrostis coarctata Ehrh. DENSE-FLOWERED BENT-GRASS. (I. F. f. 

 362a.) Glabrous. Culms tufted, erect, or decumbent at the base and often root- 

 ing at the lower nodes, 3-5 dm. tall, at length branching; leaves erect, rough on 



