20 
Racemes appressed; fruit nearly as long as the 
spikelet. 
Spikelets silky-villous, pointed........--.....---- 194. 
Spikelets glabrous, obtuse. 22222 2 22ee-e2) see eee 192; 
First glume much shorter than the sterile lemma. 
Spikelets hispid and with two crateriform glands on 
the sterile lemma. 
Spikelets not over 2 mm. long; blades not over 
Asn SOI oa. ie 2 ee i ere va shen ea aa ea 66. 
Spikelets 3.6 mm. long; blades 4 to 10 cm. long.. 67. 
Spikelets glabrous. ; 
Blades _lanceolate to ovate-lanceolate; glumes 
strongly carinate; spikelets 2.3 to 2.8 mm. 
long; tropical species. 
Blades not over 5 cm., usually 2 to 3 cm. long; 
second glume rather blunt and shorter than 
thestenletemuminaise ee 5 ee eee 64. 
Blades 5 to 11 cm. long; second glume acute, but 
slightly shorter than the sterile lemma. - - - - 
Blades linear, often elongated; glumes not carinate 
or but slightly so. 
Spikelets not over 1.5 mm. long. 
Spikelets pointed, not expanded at maturity 
by an enlarged sterile palea..-......---- 
Spikelets blunt, expanded at maturity by the 
enlarged sterile palea. 
Rachis bearing slender bristles (these want- 
ing in exceptional specimens); nodes 
miswally wall) 5. ecco cess ee cseeesee 59. 
Rachis without bristles; nodes glabrous. .-.- 60. 
Spikelets 2.5 mm. or more long. 
ASKS 8; PILOSC Rs seiig = Sie ati on ee gel ae 57. 
Axis not pilose. 
Fruit transversely rugose.-.-..---- aay Mee See 
Eruitinot mugoses Ae ee ne ee ee GSE 
Spikelets in open or sometimes in contracted or congested 
panicles, but not in spike-like racemes. 
Basal leaves usually distinctly different from those of 
the culm, forming a winter rosette; culms at first 
simple, the spikelets of the primary panicle not per- 
fecting seed, later usually becoming much 
branched, the small secondary panicles with cleis- 
togamous, fruitful spikelets ..........-- See subgenus 
Basal leaves similar to culm leaves, not forming a winter 
rosette; spikelets all fertile. 
Eruity transversely Tugose 2. 2 e)54) eee ee See 
Fruit not transversely rugose (minutely papillose- 
roughened in P. millegrana). 
CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 
P. ciliatissimum. 
P. obtusum. 
P. pulchellum. 
P. biglandulare. 
P. stoloniferum. 
P. frondescens. 
P. polygonatum. 
P. pilosum. 
P. laxum. 
P. longum. 
GEMINATA, p. 30. ~ 
P. henutomon. 
DICHANTHE- ~ 
Lium, p. 142. 
MAaxIMA, p. 78. as 
