146 
Spikelets scarcely more than 3 mm. long. 
Spikelets turgid, blunt; blades mostly less 
vamiil elms wal Ce ap tae yee =e ee 170. 
Spikelets not turgid; blades more than 1 cm. 
wide. 
Panicle narrow, branches ascending; spike- 
lets on long stiff pedicels....-......... 100. 
Panicle as broad as long, branches spreading. 
Plants glaucous; basal blades conspicu- 
Ouslyciliates 22S Sei spe a ae neo 185. 
Plants not glaucous; basal blades not cili- 
ate, orat the base only. 
Culms erect, or autumnal form leaning; 
blades symmetrical, broadly cor- 
Culms decumbent; blades usually un- 
symmetrical and faleate; narrowed 
to the scarcely cordate base-....-.-. 
Sheaths pubescent. 
Pubescence ascending or appressed. 
Spikelets 3 to 3.2 mm. long; first glume conspicu- 
OUShyAreMObe sss ys wNee UN ak ae yane see ae 142. 
Spikelets 3.5 to 4 mm. long; first glume not 
Pubescence spreading, sometimes sparse. 
Plants robust, about 1 meter high; blades usually 
D Cindy Ore Os) Wibsodassosccsosaacasseces- 189. 
Plants rarely more than 50 cm. high; blades 
rarely over 1.5 cm. wide. 
Panicles about as wide as long; blades ascend- 
ing or spreading. 
Spikelets attenuate at base, 3.5 to 4 mm. 
Spikelets not attenuate at base, not over 3.3 
mm. long. 
Spikelets 3.2 to 3.3 mm. long, blades firm; 
sheaths, or some of them, more or less 
Spikelets not over 3 mm. long; blades 
rather thin; sheaths, or some of them, 
glabrous or sparsely hispid.......---- 170. 
Panicles narrow, branches erect (sometimes 
ascending in P. wilcoxianum), or spreading 
at anthesis only; blades erect. 
Spikelets not over 3 mm. long; blades not 
OVer Giimn. wad Os. ane N oe ys haces eeaiee 168. 
Spikelets 3.7 to 4 mm. long; blades 8 to 20 
mm. wide. 
Blades papillose-hispid.............------ 174. 
Blades glabrous on both surfaces. -.-.-...--- 175. 
Spikelets less than 3 mm. long. 
Blades elongated, not over 5 mm. wide; secondary pani-_ 
cles at the base only or wanting. 
-186. 
CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 
P.. helleri. 
P. calliphyllum. 
P. mutabile. 
. P. commutatum. 
P. jooru. 
P. malacon. 
. P. oligosanthes. 
P. clandestinum. 
o 
See PEDICELLATA 
(p. 292). 
. PB. scribnerianum. 
P. helleri. 
P. wileoxianum. 
P. leibergii. 
P. xanthophysum. 
