166 



GRAMTNEAE (GRASS FAMILY) 



of the spikelet, usually subcoriaceous and rigid, several-nerved, Usually shortei 

 tiianthe florets, acute or awned ; lemmas convex or slightly keeled above, 6-7- 

 nerved, acute or awned from the apex ; palea shorter than its lemma, bristly- 

 ciliate on the keels ; grain pubescent at the summit, usually adherent to the 

 palett, — Perennials with simple culms and terminal spikes. (Name from iyp6s 

 afield, and irup6s, wheat.) 



Culms solitary or few, erect from creeping rootstocks. 



Lemmas densely pubescent » , , i, A. da&yetaohyum. 



Lemmas glabrous or scabrous. 

 Leaves flat, thin, with fine scarcely prominent nerves . , . . B. A, rep&ns. 

 Leaves becoming involute, thick, with prominent thick nerves. 



Glumes faintly nerved, long-acuminate 1, A. Smiihii, 



Glumes strongly nerved, abruptly narrowed to a rather blunt point 2, A. pungens. 

 Culms tufted ; no creeping rootstocks. 

 Awn not longer than the lemma. 



Glumes thin, widened above the middle 5. A, bijtorztm. 



Glumes firm, narrowed from below the middle , • . . , B. A, ienerum. 

 Awn about twice the length of the lemma. 



Spike nodding, symmetrical 7. A, caninwrn. 



Spike erect, one-sided ... . .... 8. .4. Bichardsonii. 



A. Smithii Rydb. (Blue-joint.) Glaucous ; culms rigid, .3-15 dm. 

 rigid, bluish green, scabrous, becoming involute, 1-2 dm. long, 

 4-6 mm. wide, basal leaves longer; spikes 0.8-1.5 dm. long; 

 spikelets 7-13-flowered, 1.2-2 cm. long, usually somewhat dis- 

 tant, glabrous or nearly so, acute, compressed, divergent, some- 

 times in pairs ; glumes acuminate, ^ or | as long as spikelet, 

 nerves usually faint ; lemmas mucronate or awn-pointed, hard, 

 faintly nerved. (A. occidentale Scribn. ; A. spicatum Scribn. & 

 J. G. Sm., as to description, not Festuca spicata Pursh.) — 

 Prairies, Mich, to Kan., and westw. July. — Rootstock aud 

 lower portion of culms gray or tawny, not bright yellow-green 

 as in A. repens. Fig. 185. 



2. A. PtJNGENS (Pers.) R. & S. Glaucous; culms slender, 

 rigid, 6-9 dm. high ; leaves 18-24 cm. long, narrowed into a 

 rigid involute point; spikes 1-1.2 dm. long, flattened parallel 

 to the rhachis ; the broad compressed spikelets along each side 

 of the rhachis, overlapping, usually alternately diverging to the 

 right and left, thus appearing i-ranlced, 7-11-flowered, 1.5-2 

 cm. long ; glumes abruptly narrowed to a 

 blunt point, 8-9 mm. long ; lemmas about 1 cm. 

 long, acute, mucronate or very short-awned. 

 {A. tetrastachys Scribn. & J. G. Sm.) — Sandy 

 seacoast of Me. July. (Nat. from Eu.) 



3. A. Ki)PENS (L.) Beauv. (ConcH, Qcitch, 

 or Quick Grass.) Bright green or glaucous, 

 3-12 dm. high ; sheaths glabrous or the lower 

 sparsely pilose ; blades flat or inrolled, sca- 

 brous or sparsely pilose above; spikes 0.5-1.6 dm. long, slender 

 or stout ; spikelets about 5-flowered, 1-1.6 cm. long ; glumes 

 8-10 mm. long, acuminate or awn-pointed, strongly nerved ; 

 lemmas about 1 cm. long, glabrous or more or less scabrous, 

 strongly nerved', pointed or terminating in an awn as much as 5 mm. long. — 

 Fields, road,sides and waste places, common. — The internodes of the long creep- 

 ing rootstock and the lower portion of the culm are colored bright greenish 

 yellow ; scales of the rootstock distant and often conspicuous. (Nat. from 

 Eu.) Fig. 186. 



4. A. dasystJchyum (Hook.) Scribn. Resembling the last, glaucous ; leaves 

 narrow and often involute ; the 5-9-flowered usually snbterete spikelets densely 

 doieny-hairy all over except the strongly nerved glumes ; lemmas thinner with 

 scarious margins, mostly long-acuminate. — Sandy shores of Lakes Huron and 

 Michigan, and northw.' Aug. 



h. A., biflftrum (Brignoli) R. & S. Culms usually decumbent at base, 8-6 dm. 



185. A. Smithii. 

 Spikelet x 8. 



186, A. repens. 

 Spikelets x %. 

 Floret X 1%. 



