630 gramine^e. (grass family.) 



7. P. pratdnsis, L. (Green or Common Meadow-Grass. Kentucky 

 Blue-Grass.) Culms sending off copious running roolstocks from the base, and 

 the sheaths smooth ; ligule short and blunt ; panicle short-pyramidal ; spikelets 3-5- 

 flowered, crowded, and most of them almost sessile on the branches, ovate-lanceo- 

 late or ovate ; lower palet b-nerved, harry along the margins as well as the keel. — - 

 Common in dry soil : imported for pastures and meadows. Indigenous in 

 mountain regions from N. Penn. northward. May -July. (Eu.) 



8. P. trivialis,. L. (Roughish Meadow-Grass.) Culms erect from a 

 somewhat decumbent base, but no distinct running rootstocks ; sheaths and leaves 

 more or less rough-; ligule oblong, acute ; panicle longer or with the branches more 

 distant ; spikelets mostly 3-flowered, broader upwards ; lower palet prominently 

 5-nerved, naked at the margins: otherwise nearly as in the preceding. — Moist 

 meadows, &c, July. (Nat. from Eu.) 



■s- -t- Spikelets fewer and more scattered, on slender pedicels: plants soft and smooth, 



flowering early. (No running rootstocks, except in No. 13.) 

 ++ Spikelets small (l"-2" long), pale green, rather loosely 2 - 4-flowerect I: flowers 



oblong, obtuse : lower palet scarcely scarious-tipped : culm-leaves lance-linear, acute, 



l'-3' long. 



9. P. sylvestris. Gray. Culm flattish, erect; branches of the oblong-pyram- 

 idal panicle short, numerous, in fives or more ; lower palet villous on the keel for 

 its whole length, and on the margins below the middle, sparingly webbed at the base. 

 — Rocky woods and meadows, W. New York, Penn. and Virginia to Wisconsin, 

 Kentucky, and southward. June. 



10. P. debilis, Torr. Culms terete, weak; branches of the small panicle 

 few and slender (the lower l|'-2' long to the few spikelets), in pairs and threes; 

 flowers very obtuse, smouth and glabrous, except a sparing web at their base. — 

 Rocky woodlands, Rhode Island and N. New York to Wisconsin. May. 



++ ++ Spikelets 2" long, light green: oblong-lanceolate flowers and both glumes acute. 



11. P. als6d.3S, Gray. Leaves rather narrowly linear, acute, the upper- 

 most (2^' -4' long) often sheathing the base of the narrow and loose panicle, the 

 capillary branches of which are appressed when young, and mostly in threes or 

 fours ; lower palet very obscurely nerved, villous on the keel below, and with a 

 narrow cobwebby tuft at its base, otherwise glabrous. ( P. nemoralis, Torr. 8f 

 Ed. 1 : but wholly different from the European species of that name.) — Woods, 

 on hillsides, New England to Penn. and Wisconsin. May, June. 



++++++ Spikelets larger (3'' -4" long), pale green, rarely purple-tinged, few and 

 scattered at the extremity of the long and capillary branches {mostly in pairs or 

 threes) of the very diffuse panicle : flowers 3-6, loose, oblong and obtuse, as is 

 the larger glume: lower palet conspicuously scarious at the apex, villous below the 

 middi'i on the keel and margins: culms flattish, smooth. 



12. P. fiexuosa, Muhl. (not of Wahl.) Culms l°-3° high, tufted; its 

 leaves all linear (2' -5' long) and gradually taper-pointed; panicle very effuse (its 

 branches 2' -4' long to the 4-6-fiowered spikelets or first ramification); loiver 

 palet prominmily nerved, no web at the base. (P. autumnalis, Muhl. in Ell. P. 

 campy le, Sclinlt.) — Dry woods, Virginia, Kentucky, and southward. Feb. - 

 May. — Wrongly confounded with the last, but near it. P. autumnalis is an 



