GRASS FAMILY. I 59 



35. AGROSTIS L. Sp. PI. 6. 1753. 

 [TRICHODIUM Michx. Fl. Bor. Am. i: 41. 1803.] 



Annual or perennial tufted grasses with flat or bristle-like leave* and paniculate iafiotm 

 cence. Spikelets i -flowered. Scales 3; the 2 outer empty, membranous, 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. Stamen* anally j. 

 Styles distinct, short. Stigmas plumose. Grain free, enclosed in the scale. Seed adhnt 

 to the pericarp. [Name Greek, referring 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 North America, 



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



Palet inconspicuous, minute or wanting. 



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



ala. 

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



ends. 

 Third scale awned. 



Awn very finely filiform and flexuous, at least twice the length of the *pikelet which 



is Ji" long. 5. A. Klltothama. 



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

 Branches of the panicle generally ascending; spikelets i" long. 



L. A. camina 

 Branches of the panicle usually spreading; spikelets iX"-i}< Ion*. 



5. A. rubr*. 

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



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



long. 6. A. f*rrm*amt. 



Culms and leaves erect. 



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



the spikelets crowded at the extremities. 



Spikelets K"-i" long; leaves short. 7. A. kifmalit. 



Spikelets iK"-iM" long; leaves elongated. . A. altnstma. 



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



Spikelets about i" long; a grass of low elevations. 9. A. intrrmrdia. 



Spikelets iK"-iM" long; a high mountain grass. 10. A. Novae-Attglim*. 



i. Agrostis alba L. Red-top. Fiorin. Herd's-grass. (Fig. 362.) 



Agrostis alba L. Sp. PI. 63. 1753. 



Agrostis vulgaris With. Bot. Arr. Brit. PI. 

 Ed. 3, 132. 1796. 



Agrostis alba var. vulgaris Thurber in A. 

 Gray, Man. Ed. 6, 647. 1890. 



Culms %'-2% tall, erect or decumbent 

 at the base, often stoloniferous, simple, 

 smooth and glabrous. Sheaths usually 

 shorter than the internodes, often crowded 

 at the base of the culm; ligule 4" long or 

 less; leaves 2 / -8 / long, i // -3 // wide, sca- 

 brous; panicle a'-o/ in length, contracted 

 or open, green or purplish, the branches 

 ascending or erect, the lower i'-$' long; 

 spikelets \"-\% ff 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 North Amer- 

 ica, extensively cultivated for fodder. Natu- 

 ralized from Europe, and perhaps also native 

 northward. We have been unable satisfac- 

 torily to separate A. svlvatica I,, from this. 

 July-Sept. 



II 



