Genus 47. 



GRASS FAMILY. 



2. Calamovilfa brevipilis (Torr.) Hack. Short- 

 haired Reed-grass. Purple Bent-grass. Fig. 514. 



Arundo brevipilis Torr. Fl. U. S. 1 : 95. 1824. 

 Calamagrostis brevipilis Beck, Bot. North. & Mid. St. 401. 



1833. 

 Calamovilfa brevipilis Hack. True Grasses 113. 1890. 



Glabrous and smooth or very nearly so, culms 2°-4° 

 tall, erect, simple. Sheaths shorter than the internodes ; 

 ligule a ring of very short hairs; blades 6'-i2' long, ij" 

 wide or less, attenuate into a long slender involute tip, 

 smooth beneath, slightly scabrous above ; panicle open, 

 5'-io' in length, the branches ascending, the lower 2'-^.' 

 long; spikelets 2"-2i" long; scales acute, scabrous 

 toward the apex, the outer unequal, the first one-half as 

 long as the second; third scale exceeding the second, 

 pubescent on the lower half of the keel; basal hairs one- 

 third the length of the scale; palet nearly equalling the 

 scale, pubescent on the lower half of the keel. 

 - In swamps, pine barrens of New Jersey. Aug.-Sept. 



3. Calamovilfa gigantea (Nutt.) Scribn. & 

 Merr. Giant Reed-grass. Fig. 515. 



Calamagrostis gigantea Nutt. Trans. Am. Phil. Soc. II. 



5: 143- 1837- 

 Calamovilfa gigantea Scribn. & Merr. Circ. U. S. Dep. 



Agr. Agrost. 35 : 2. 1901. 



A stout glabrous perennial with stout creeping 

 rootstocks, rigid often involute leaf-blades, and 

 large open panicle. Culms 3°-6° tall; leaf-sheaths 

 exceeding the internodes; blades up to' 1° long or 

 more; panicle i°-2i° long, the spreading or ascend- 

 ing branches naked at the base, the longer up to 1° 

 long; spikelets 3i"-4" long, the empty scales acute, 

 the first shorter than the second, the third scale a 

 little longer or shorter than the second scale, long- 

 hairy on the back and keel, the basal hairs copious. 



In sandy places, Kansas to Arizona. 



48. APERA Adans. Fam. PI. 2 : 495. 1763. 



Annual grasses with narrow flat leaf-blades, and 

 ample open or contracted panicles. Spikelets i-flow- 

 ered, small, the rachilla prolonged beyond the flower 

 into a bristle. Scales 3; the 2 outer empty, unequal, 

 thin, membranous, keeled, acute; the third scale a little shorter, membranous, bearing a long 

 slender awn inserted just below the shortly 2-toothed apex; palet a little shorter than the 

 scale, 2-keeled, 2-toothed. Stamens 3. Styles distinct, short. Stigmas plumose. Grain 

 narrow, free, included in the scale. Seed adherent to the pericarp. [Greek, signifying not 

 mutilated, whole or entire; application uncertain.] 



Two species, natives of Europe and western Asia. 

 Type species : Agrostis Spica-venti L. 



i. Apera Spica-venti. (L.) Beauv. Silky 

 Bent-grass. Windlestraw. Fig. 516. 



Agrostis Spica-venti L. Sp. PI. 61. 1753- 

 Apera Spica-venti Beauv. Agrost. 151. 1812. 



Culms i°-2° tall, erect, simple, slender, smooth 

 and glabrous. Sheaths usually longer than the in- 

 ternodes, the upper one generally including the base 

 of the panicle; ligule l"-3" long; blades i'-f long, 

 ¥'-2" wide, scabrous; panicle 3'-o/ in length, the 

 branches erect or ascending, capillary, 1J-3' long; 

 outer scales of the spikelet i"-ii" long, acute, 

 smooth and shining; third scale hairy or nearly 

 smooth, bearing a dorsal scabrous awn 3"-4" long; 

 rudiment at the end of the rachilla less than I" long. 



In waste places and on ballast, Maine to southern 

 New York and Pennsylvania. Adventive from Europe. 

 Wind-bent, Wind-grass, Corn-grass. June-July. 



