640 GRAMINE^. (grass FAMILY.) 



48. DANTHONIA, DC. Wild Oat-Grass. (PI. 12.) 



Lower palct (oblong or ovate, roundcd-cylindraccous, 7-9-nen'ed) hearing 

 between the sharp-pointed or awn-like teeth of tlie tij) an awn composed of the 

 3 middle nerves, which is flattish and spirally twisting at the base : otherwise 

 nearly as in Avena. Glumes longer than the imbricated flowers. Ours peren- 

 nials, l°--J° high, with narrow and soon involute leaves, hairy sheaths bearded 

 at the throat, and a small simple panicle or raceme of about 7-flowcred spikelets. 

 (Named for Dnnlhuine, a French botanist.) 



1. D. spicata, Beauv. Culms tufted, low; leaves short, very narrow; 

 spikelets few, 3" -5" long ; lower jicdet loosili/ hniri/, its teeth short and pointless. — 

 Dry ami sterile or rocky soil. June -Aug. 



2. D. serieea, Nuit. Taller and not tufted (1°- 3° high); leaves larger ; 

 spikelets more numerous and i)anicled, 6" -9" long; lower palet very sUky-viilous, 

 tipped with slender awn-pointed teeth. — Dry or moist sandy soil, Southern Massa- 

 chusetts {Dr. liobbins), New Jersey {C. E. Smith, C. F. Parker), and southward: 

 rare. June. 



49. AVENA, L. O.vx. (n. 12.) 



Spikelets 2 - many-flowered, panicled ; the flowers herbaceo-ehartaceons, o^ 

 becoming harder, of firmer texture than the large and mostly unequal glumes; 

 the uppermost impei-feet. Lower palet rounded on the back, mostly 5-11- 

 nerved, bearing a long usually bent or twisted awn on the back or below the 

 acutely 2-cleft tip proceeding from the midnervc only. Stamens 3. Grain ob- 

 long-linear, grooved on one side, usually hairy at least at the top, free, but in- 

 vested by the upper palet. (The classical Latin name.) — The Common' Oat 

 (A. SATiVA, L.) represents the large-flowered annual species of the Old World. 

 The following arc smaller-flowered, indigenous perennials. 



L A. striata, Michx. Glubrous and smooth throughout, slender (\^-2° 

 high); leaves narrow; ligulc short, truncate; panicle simple, loose; spikelets 

 (6" long) on capillary pedicels, 3-6-flowered, much exceeding the searious- 

 margined purple acute glumes; the loiccr ylnme 1-, uppir ^-nerved; rhaehis 

 smooth ; Jlowirs short-hmrded at the hose; lower palet 7-nerved, much longer than 

 the ciliate-fringed upper one (4" long), mostly shorter than its soon bent or 

 divergent awn, which rises just below the tapering very sharply cuspidate 

 2-cleft tip. (Trisetum purpuraseens. Ton:) — Rocky, shaded hills, N. New 

 England, New York, and northwestward. June. 



2. A. Smithii, T. C. Porter, n. sp. Taller (21°- 4^° high), rather stout ; 

 leaves broadly linear (.T'-G" wide) and taper-pointed, flat, and with the sheaths 

 and culm rdrorseli/ scuhroiis; ligule elongated, acute; panicle larger (C'-12' 

 long), the few branches at length .spreading; glumes slightly ptirplish, scabrous 

 on the nerres, of which there are 3 in the lower and 5 in the upper; rhachis :ni- 

 nutely his])id; flowers (3 -.5) not luiiri/-tiifled at the base; awn one third or half 

 the length of the 7-nerved palet, straight. — Isle lloyalc, Keweenaw Point, Lake 

 Sujierior, Lol>bins. Woods near Sault Ste. Marie, C. E. Smith, for whom the 

 species is named. April, May. — To be compared with the Siberian A. eallosa, 

 Turczaninow, which was referred to A. striata bv Trinius. 



