POACEAE 57 



node ; pedicellate spikelet smaller and of 2 scales, or sometimes staminate and as long as 

 the linear pedicel. 



In swampy places, Florida. Fall. 



4. Manisuris rugosa (Nutt. ) Kuntze. Stems tufted, much compressed, 7-12 dm. 

 tall, stout : leaf-sheaths much flattened, broad, keeled ; blades 4 dm. long or less, 6 mm. 

 wide or less : racemes exserted or somewliat included at the base, 5-8 cm. long, straight or 

 a little curved, the rachis internodes usually much contracted at the base and puberulent : 

 sessile spikelet 3.5-4.5 mm. long, about equalling or a little exceeding the internodes, the 

 first scale strongly transversely wrinkled, the wrinkles much elevated and often extending 

 across the entire width of the scale, the longitudinal ridges usually rather prominent, often 

 2-toothed at the obtuse apex ; pedicellate spikelet of 2 scales, | as long as the clavate 

 puberulent pedicel or less. \_Rottboellia i-iigosa Nutt. Rottboellia corruc/nfa Baldw. ] 



In wet places, Delaware and Maryland to Florida and Texas. Summer and fall. 



5. Manisuria tessellata (Steud. ) Scribn. Stems tufted, much compressed, 8-12 dm. 

 tall, stout : leaf-sheaths much flattened, broad, keeled ; blades 4 dm. long or less, 3-8 

 mm. wide : racemes finally exserted, 6-12 cm. long, straight, the rachis barely if at all 

 contracted at the nodes : sessile spikelet about 5 mm. long, a little exceeding the inter- 

 node, the first scale deeply pitted, the pits quadi-angular : pedicellate spikelet of 1 or 2 

 scales, about J as long as the straight linear pedicel which is shorter than the sessile spike- 

 let. [Rottboellia corrugata C'hapm., not Baldw.] 



In low pine lands, Alabama to Louisiana. Summer and fall. 



5. HACKELOCHLOA Kuntze. 



Annual grasses, with brandling stems, flat leaf-blades and terminal and axillary short 

 spikes which are sometimes partially included in the sheaths. Spikelets in pairs in excava- 

 tions at the rachis-joints, one sessile, 1-flowered, the other pedicellate, flowerless. Scales 

 of the sessile spikelet 4, awnless, the outermost empty, firm, globose, pitted, covering the 

 excavation in the rachis, the second small, concave, thin, somewhat rigid, the third empty, 

 the fourth small, thin, hyaline, enclosing a perfect flower and sometimes also a minute 

 palet. Stamens 3. Styles distinct. Stigmas plumose. {_3fanisuris Sw^ , not L. ] 



1. Hackelochloa granulans (L. ) Kuntze. Stems tufted, 2-10 dm. tall, finally 



much branched : leaf-sheaths pajnllose-hirsute ; blades 1.5 dm. long or less, 3-15 mm. 



wide, papillose-hirsute on both surfaces, ciliate on the margins : racemes 1-2 cm. long, the 



peduncles hirsute : sessile spikelet about 1 mm. in diameter ; pedicellate spikelet about 2 



mm. long, sterile, consisting of 2 scales. [Manisuris granularis Sw. ] 



In cultivated and waste places, Georgia and Florida to Arizona. Also in all tropical regions. 

 Summer and fall. Lizard-tail Grass. 



6. TRACHYPOGON Nees. 



Tall perennial grasses, with long narrow leaf-blades and spike-like terminal racemes. 

 Spikelets 1-flowered, one almost sessile and staminate, or if perfect, sterile, the other ped- 

 icellate and enclosing a perfect flow^er. Scales usually 4 ; the first scale rigid, awnless, en- 

 closing the rest, the second somewhat resembling the first but smaller and thinner, the 

 third scale very thin and hyaline ; fourth scale in the sessile spikelets very thinly hyaline, 

 awnless, in the pedicellate spikelet very narrowly hyaline at the base, and produced into a 

 very long contorted awn which is geniculate above. Palet minute or wanting. Stamens 

 3. Styles distinct. Stigmas plumose. 



1. Trachypogon secundus (Presl) Nash. Stems tufted, 8-10 dm. tall, simple, the 

 nodes barbed : leaf-blades erect, 1-3 dm. long, about 3 mm. wide, hirsute on the upper 

 surface : racemes 1-2 dm. long, the rachis glabrous : short -pedicellate spikelet about 7 mm. 

 long, the long-pedicellate one about 9 mm. in length, the first scale of both copiously pu- 

 bescent with rather long ascending liairs, the awn of the latter 4 -6 cm. long, twisted at 

 the base and geniculate, pubescent below wdth long nearly erect hairs which become much 

 shorter toward the summit. [Heteropogon secundus Presl.] 



In dry soil, Texas to Arizona, south to Mexico. Summer and fall. 



7. ELIONTJRUS H. & B. 



Tall and branched, or low and tufted grasses, with often elongated leaves, and terminal 

 spikes. Spikelets in pairs in excavations at the rachis-nodes ; one sessile, 1-flowered, or 

 rarely 2-flowered ; the other pedicellate, sometimes enclosing a flower. Scales 4, awnless. 



