648 GRAMINE^E. (GRASS FAMILY.) 



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

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

 the spikelets more ovoid, often smooth ; the lower flower (always ? ) 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' - 1 1 long) ; spikelets only about $" long, ovoid, smooth or 

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

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

 southward. July - Sept. 



14. P. xanthoph^TSUIQ, 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 ll-nerved; panicle long-peduncled, very simple, the appressed branches 

 bearing a few roundish-obovate spikelets (about l" 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. viscidum, 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 l" 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. paucifldrum, Ell. ? Culms upright, at length much branched and 

 reclining (l-2 long), roughish; leaves lanceolate (3' -5' long by i'*'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 bristly throughout with similar 

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

 spikelets about l" long ; 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 Jlat 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 upper one. Founded on an autumnal 

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



