POACEAE 
XV. BICKNELLIANA 
vspikelets tufted stems and open panicles with few 
spi ts 
XVI. NUDICAULIA 
Plant with erect or partly decumbent stems, the panicles 
with spreading branches. 
XVII. DICHOTOMA 
Nodes, at least the pe bearded. 
Spikelets 1.5-1.6 mm. long, glabrous (occasional in- 
dividuals with Poss. Spikelets). 
Spikelets 2 mm. ore long. 
RE glabrous, 2 mm. long: autumnal form 
top-heavy-reclining. 
Spikelets pubescen 
Leaf-blades all velvety : autumnal form spar- 
ingly branched. 
Leaf-blades glabrous, or only the lower pubes- 
cent o ve vety: autumnal form freely 
branchin 
Spikelets 2 mm. long: autumnal form pro- 
füsalv DOE 
Spikelets 2.2 ore long: autumnal 
form jess p e branching. 
MAS P ud Sheaths and all nodes pu- 
ee sheaths and upper nodes glabrous. 
Nodes not Usi Use nodes pubescent in P. barbu- 
um 
Spikelets” pubes 
Stem EIE prem becoming vine-like. 
Stems d ‘prostrate, vine-like : branches divari- 
Plants HARE. Stems lax: spikelets not 
ng. 
Plants B E Stems stiff: spikelets 
ng. 
aD ao us. 
m soon prostrate. 
“Pla an bright-green ; stems lax: spikelets not 
ver 2.1 mm. lon 
Plant pon -green : ' Stems Stiff: spikelets 2.5 
Stem erect, or the autumnal form topheavy, 
` never prostrate. 
Spikelets not over 1.6 mm. long: panicles nar- 
row: plants ipiis bluish- -green. 
Spikelets 2 mm. or more long: panicles open. 
ee erect ans Spikelets turgid, 
ongly nerved : plants grayish olive- 
Leaf-blades spreading: spikelets not 
Spikelets 2.2 more long, 
poi inted : sheaths. here pale glan- 
USE spots, ` 
Spikelets not over 2 mm. long, not 
e 
Autumnal form erect, branched like 
Autumnal iori topheavy-reclin- 
ing: primary leaf-blades 6-10 
mm. wide: second glume equal- 
ling fruit and sterile lemma. 
XVIII. SPRETA 
Pa anicle narrow, one-fourth to one-third as wide as long. 
Panicle open, two-thirds as wide as long, or more. 
Spikelets 1.5 mm. lon 
Spikelets 1.3 mm. Jones. or less. 
Stem and leaf-sheaths glabrous. 
5 
47. 
48. 
60. 
50. 
51. 
02. 
53. 
53. 
54. 
57. 
58. 
P. Bicknellii. 
P. nudicaule. 
. P. microcarpon. 
P. barbulatum. 
P. annulum. 
P. nitidum. 
P. mattamuskeetense. 
P. Clutei. 
P. Clutei. 
P. lucidum. 
P. sphagnicola. 
. P. lucidum. 
. P. sphagnicola. 
. P. caerulescens. 
P. roanokense. 
P. yadkinense. 
. P. dichotomum. 
. P. barbulatum. 
. P. spretum., 
. P. Lindheimeri, 
. P. longiligulatum. 
