596 CLXI. GRAMINEjE. AGROSTIS 



5. A. STRICTA. Michx. Upright Aristida. 



St. strictly erect, cccspitose, branched, 2 3f high; Ivs. straight, erect, 

 pubescent, linear, convolute above ; panicle long, loosely racemose; spikdets ap- 

 pressed ; glumes unequal, very acute ; lower palecc hairy at base ; awns twice as long 

 as the paleoc, spreading, the middle one the longest. % Penn. to Car.W. to Mich 



2. STIPA. 



Lat. stipa, a foot-stalk ; alluding to the stipitate fruit of some of the species. 



Glumes 2 ; palese mostly 2, shorter than the glumes, the lower 

 with a long awn at the apex, the upper entire ; awn jointed at the 

 base, deciduous ; caryopsis striate. 



1. S. AVENACEA. Feather Grass. 



St. naked above ; 2 3f high ; Ivs. smooth, striate, setaceous, chiefly radi 

 cal; panicle spreading, somewhat 1-sided, 4 6' long, at length diffuse, branches 

 capillary, solitary and in pairs ; glumes nearly equal, mucronate, as long as the 

 dark brown, cylindric fruit ; scales 2, lanceolate ; awn twisted, 23' in length. 

 % N. Y. to Car. 



2. S. JUNCEA. Pursh. Rush-kavcd Feather Grass. 



St. 2 3f high ; Ivs. convolute-filiform, smooth inside, long ; panicle loose ; 

 glumes loose, filiformly acuminated to more than twice the length of the fruit ; 

 fr. attenuated at base into a stipe which is a third of its length, stipe acute, 

 pubescent; palece obtuse, distinctly articulated to the awn, which is smooth and 

 slender, scarcely contorted and 4 6' in length. 1|_ Prairies, 111., Mo. When 

 in fruit, the pungent stipe adheres to everything that comes in its way. Aug. 



3. S. CANADENSIS. Lam. 



Lvs. setaceous; panicle small; glumes smooth, ovate-obtuse, as long as 

 the pubescent fruit ; awn thick and short. 7J. Amherst, Mass, Dewey. Neither 

 this nor the preceding species is common or of much value in agriculture. 



3. PIPTATHERUM. Palis. 



Gr. jrtTJ-rci), to fall, -8-epoj, harvest. 



Panicle racemed ; glumes membrariaceous, longer than the ellipti- 

 cal, cartilaginous palese ; lower palca awned at the tip ; scales ovate, 

 entire ; caryopsis coated. 



P. NIGRUM. Torr. (Oryzopsis melanocarpa. Muhl.) Black-seeded Millet. 

 St. erect, simple, leafy,- 18 24' high ; panicle simple, flexuous, few- 

 flowered ; spikelels racemose, ovoid-lanceolate ; glumes acuminate, mucronate, 

 5 6" in length, smooth ; palece hairy, nearly black when ripe, the lower one 

 tipped with an awn an inch in length; fruit black. 1|_ Rocky hills, N. Eng. 

 to Ky., frequent. Aug. 



4. ORVZOPSIS. Rich. 

 Named for its resemblance (ot//ts) to the genus Oryza.. 



Panicle racemed ; glumes 2, subequal, loose, obovate, awnless ; 

 palese 2, cylindric-ovate, hairy at base ; scales linear-elongated. 



O. ASPERIFOLIA. Michx. Mountain Rice. 



St. nearly naked, purple at base, 10 20' high; Ivs. subradical, erect, 

 rigid, pungent at the point, nearly as long as the stem,, cauline ones few and 

 very short ; spikelets in a racemose, simple, flexuous panicle, 1 2 upon each 

 branch ; glumes abruptly acuminate ; palece white, the lower one with a long 

 bent awn. Woods, Free States, N. to Subarctic Am. Leaves green through 

 the winter. Caryopsis white, about as large as rice, farinaceous. May. 



TRIBE 2. AGROSTIDEJE. Inflorescence panicled, rarely spiked. Spike- 

 lets solitary, 1-flowered. Glumes and paleae of nearly similar texture, usu- 

 ally carinate. 



5. AGROSTIS. 



Gr. aypoj, a field ; it being eminently an occupant of fields and pastures. 



Inflorescence paniculate ; glumes 2, acute, subequal, the lower one 



