Part 3, 1915] 



POACEAE 



205 



XIII. Parviglumia. 



Fruit with scattered appressed silky hairs. 



Culms creeping, with ascending flowering branches, not more than 0.5 



meter tall; leaf -blades falcate. 

 Culms clambering, usually 1~3 meters long; leaf -blades not falcate. 

 Panicles 2.5-7 cm. long; leaf -blades not more than 1 cm. wide, 



symmetric at base. 

 Panicles 10-15 cm. long; leaf-blades 1.2-2.5 cm. wide, asymmetric 

 at base. 

 Fruit glabrous. 



Spikelets about 2 mm. long, glabrous. 

 Spikelets more than 3 mm. long, hispid. 



XIV. Verrucosa 



XV. Trichoidia 



Spikelets pyriform, attenuate at base, glabrous. 

 Spikelets obovate -elliptic, pubescent. 



One species. 



XVI. UrviixEana , 



One species. 



XVII. Parvifowa. 



One species. 



XVIII. Haenkeana, 



Spikelets about 1.5 mm. long, acute 

 Spikelets about 2 mm. long, obtuse. 



XIX. MlIXEGRANA 



One species. 



XX. Giaitinosa. 



One species. 



XXI. Rtjdgeana. 



One species. 



XXII. Megista. 



XXIII. Depauperata. 

 Spikelets about 3.5 mm. long, beaked. 



Spikelets 3 mm. long or less (sometimes 3.2 mm. long in P. perlongum), 

 not beaked. 

 Culms single or few in a tuft; spikelets turgid, blunt, 2.7-3.2 mm. long; 



prairie plants. 

 Culms in large tufts; spikelets not turgid, 2.2-2.7 mm. long; plants of 

 dry woods. 

 Leaf -sheaths pilose; spikelets 2.2—2.7 mm. long, pilose. 

 Leaf-sheaths glabrous; spikelets 2.2-2.3 mm. long, glabrous or 

 sparingly pilose. 



XXIV. Laxifxora. 



79. P. Schmitzii. 



78. P. virgultorum, 



80. P. Schijfneri. 



81. P. parviglume. 



82. P. verrucosum. 



83. P. brachyanthum. 



84. P. pyrularium. 



85. P. trichoides. 



86. P. Urvilleanum. 



87. P. parvif olium. 



88. P. Haenkeanum, 



89. P. trichanthum. 



90. P. Millegrana. 



91. P. glutinosum. 



92. P.Rudgei. 



93. P. megislon. 



94. P. depauperatum 



95. P. perlongum. 



96, P. linear if olium. 



97. P. Werneri. 



Leaf -sheaths retrorsely pilose; spikelets papillose-pilose. 



Leaf -blades glabrous or nearly so on the surface and margin ; spikelets 



2.2 mm. long. 08. P. laxifiorum. 



Leaf -blades ciliate, more or less pilose on the surface ; spikelets 2 mm. 



long. ^ 99. P. xalapense. 



Leaf -sheaths not retrorsely pilose ; spikelets pubescent or glabrous. 



Spikelets pubescent, about 2 mm. long. 100. P. ciliaium. 



Spikelets glabrous. 



Leaf -blades glabrous on the surface. 101. P. 



Leaf -blades pilose on the surface. 102. P. 



polycaulon, 

 slrigosum. 



104. 

 105. 



P. chrysopsidif olium, 

 P. consanguineum. 



XXV. Angustifolia. 



Nodes bearded; plants grayish-villous ; autumnal leaf -blades flat. 

 Spikelets 2 mm. long. 

 Spikelets 2.5-2.8 mm. long. 

 Nodes not bearded; plants villous only at base, or nearly glabrous; 

 autumnal leaf -blades involute or flat. 

 Autumnal blades flat; lower panicle-branches spreading or deflexed. 106. P. an gustif olium. 

 Autumnal blades involute; lower panicle-branches more or less 

 ascending. 

 Spikelets 3.3-3.5 mm. long, pointed. 



Spikelets less than 3 mm. long, not pointed, or obscurely so. 

 Plants pubescent, at least on the lower half. 



107. P. fusiforme. 



