648 GRAMINE^E. (GRAS'S FAMILY.) 



minal panicle more or less enclosed in the sheaths, or with the terminal one at length 

 long-pedurxled (P. pedunculatum, Torr.) : — otherwise resembling No. 11 ; but 

 the spikelets more otoid, often smooth ; the lower flower (always 1 ) neutral. — Low 

 thickets and river-banks : common. June - Sept. 



13. P. microcarpon, Muhl. Culm and sheaths as in No. 11 ; the broadly 

 lanceolate leaves nearly similar, but longer in proportion and less pointed, not 

 dilated at the rounded bristly-ciliate base, very rough-margined, the upper sur- 

 face roughish ; panicle soon exserted on a slender peduncle, very many-flowered, 

 narrowly oblong (3' -7' long) ; spikelets only about £" long, ovoid, smooth ot 

 smoothish ; lower glume orbicular and very small. (P. multiflorum, Ell. ? not 

 of Puir.) — Dry or moist thickets, Pennsylvania and Michigan to Illinois, and 

 southward. July - Sept. 



14. P. xanthophysum, Gray. Culm simple, or at length branched near 

 the base (9' -15' high) ; sheaths hairy; leaves lanceolate, very acute (4' -6' long by 

 %' wide), not dilated at the ciliate-bearded clasping base, smooth except the margins, 

 strongly 9 - 1 1 -nerve d ; panicle long-peduncled, very simple, the appressed branches 

 bearing a few ruundish-obovate spikelets (about 1^" long) ; lower glume ovate, 

 acutish, one third or half the length of the 9-nerved upper one. — Dry sandy 

 soil, Maine to Wisconsin, and northward : rare. June. — Plant yellowish-green : 

 spikelets minutely downy : sterile flower sometimes staminate. 



15. P. viseidlim, Ell. Culms upright or ascending, at length much 

 branched, leafy to the top, densely velvety -downy all over, as also the sheaths, with 

 reflexed soft and often clammy hairs, except a ring below each joint ; leaves 

 likewise velvety, lanceolate (£[ wide), 11 - 13-nerved; panicle spreading, the lat- 

 eral ones included; spikelets obovate 1" or 1^" long, downy; the roundish lower 

 glume scarcely one fourth the length of the 7 -nerved upper one. — Damp soil, 

 New Jersey to Virginia, and southward. Aug. 



16. P. paucifldmm, Eli. ? Culms upright, at length much branched and 

 reclining (l°-2° long), roughish; leaves lanceolate (3' - 5' long by £'-£'wide), 

 rather faintly 9-nerved, hairy or smooth, fringed on the whole margin or next the 

 base with long and stiff spreading hairs, the sheaths brisily throughout with similar 

 hairs ; panicle open, nearly simple, bearing few tumid-obovate hairy or smoothish 

 spikelets about l^" lung ; lower glume roundish, about half or a quarter of the 

 length of the upper one. — Wet meadows and copses, E. Massachusetts to Wis- 

 consin, and southward. June, July. — Distinguished by its much larger spike- 

 lets, more nerved leaves, and coarser aspect, from any form of the next. It has 

 probably been described under several names, some of them earlier than Elliott's. 



++ ++ Leaves linear or lanceolate, with few or indistinct primary nerves. 



17. P. dich6tomum, L. ! Culms (8' -20' high) at first mostly simple, 

 bearing a more or less exserted spreading compound, panicle (l'-3' long), and 

 lanceolate flat leaves (those tufted at the root usually ovate-lanceolate and very 

 short, thickish) ; but commonly branching later in the season, the branches often 

 clustered, and bearing nearly simple and included small panicles ; spikelets ^'' to 

 about 1" long; oblong-obovate, downy or smooth; lower glume roundish, one third 

 or a quarter the length of the 5-7-nerved uppier one. — Founded on an autumnal 

 state of the species, much forked and with densely clustered lateral branchlets 



