POACEAE 105 



33. SACCIOLEPIS Nash. 



Perennials with Hat leaf-blades and contracted dense panicles. Spikelets numerous. 

 Scales 4, the 3 outer membranous ; 2 outer scales empty, the first scale small and narrow, 

 the second one large and broad, 11-nerved, saccate and gibbous at the base, the third scale 

 enclosing a palet and staminate flower, the fourth scale chartaceous, finally indurated, about 

 jf as long as the second scale, enclosing a palet of similar texture and a perfect flower. 

 Stamens 3. Styles distinct. Stigmas plumose. 



1. Sacciolepls gibba ( Ell. ) Nash. Stems erect or ascending, usually rooting at the 

 lower nodes, finally dichotoniously branched, 3-20 dm. long : leaf-sheaths papillose-hirsute, 

 at least the lower ones ; blades lanceolate, spreading or ascending, long-acuminate, some- 

 times hirsute on one or both surfaces, 4-20 cm. long, 4-22 mm. wide : panicle contracted, 

 6-30 cm. long, 1.5-2 cm. wide : spikelets 4—5 mm. long, ovate-lanceolate. \^Panicum 

 glbhum Ell.] 



In swamps and low grounds, Virginia to Tennessee, Missouri, Florida and Louisiana, chiefly 

 along the coast. Also in Cuba. Summer and fall. 



34. 'STEINCHISMA Raf. 



Perennial tufted grasses, with erect stems, flat leaf-blades and loose open panicles. 

 Spikelets 1-ilowered, the 3 outer scales membranous, the third scale bearing in its axil a 

 much enlarged and inflated papery palet which exceeds in length the fourth scale ; first 

 scale short, the second one about as long as the spikelet ; fourth scale indurated in fruit 

 and enclosing a palet of similar texture and a perfect flower. Styles long, united only at 

 the base. Stigmas plumose. 



1. Steinchisma iiians (Ell. ) Nnsli. Glabrous. Stems erect, 3-8 dm. tall, sometimes 

 creeping at the base : leaf-blades 7-13 cm. long, 2-6 mm. wide, acuminate, usually erect : 

 panicle 7-20 cm. long, its branches few, generally spreading : spikelets about 2 mm. long. 

 [Panieum Mans Ell.] 



In moist ground, North Carolina to Missouri, Florida and Texas. Summer and fall. 



35. CHAETOCHLOA Scribn. 



Annual or perennial grasses, with usually flat, sometimes complanate, leaf-blades and 

 dense terminal cylindric spike-like or narrowly thyi-soid panicles. Spikelets with one or 

 a cluster of 2-several sterile barbed bristle-like persistent branches. Scales 4, the 3 outer 

 membranous, the first often very short and together with the larger second one empty, the 

 third scale frequently longer than the second, empty, or rarely enclosing a palet and also 

 sometimes a staminate flower, the fourth scale usually shorter than the spikelet, charta- 

 ceous, glabrous, shining, often transversely rugose, finally indurated, obtuse, enclosing 

 a shorter palet of similar texture and a perfect flower. Stamens 3. Styles distinct, 

 elongated. Stigmas plumose. [^Se^ar ('a Beauv., not Achar.] Foxtail. Foxtail Gra.ss. 



Inflorescence with the spikelets racemosely arranged : bristles 5-16 at the base of 

 each spikelet, involucrate. 

 Annual ; bristles tawny orange. 1. C. f/lauca. 



Perennial, from branching rootstocks : bristles green, yellowish green or 

 purple. 

 Inflorescence stout : bristles usually exceeding twice the length of the 

 spikelet. 

 Rootstocks slender : leaf-blades elongated. 



Second scale of the spikelet 5-7-nerved : leaf-blades sometimes with 



a few scattered hairs near the base on the upper surface. 2. C. imberbis. 



Second scale of the spikelet 3-iierved : leaf-blades glabrous. 3. C. versicolor. 



Rootstocks stout : leaf-blades short, thick and firm, grayish green. 4. C. occidentalis. 



Inflorescence slender : bristles once or twice as long as the spikelet. 



Leaf-blades linear-lanceolate, short. 5. C. purpurascens. 



Leaf-blades linear, elongated. 6. C. gracilis. 



Inflorescence with the spikelets in clusters or on branches : bristles 1-3 at the base 

 of each spikelet. not involucrate. 

 Bristles downwardly barbed. 7. C. vertidllata. 



Bristles upwardly barbed. 



a. Second scale of the spikelet as long as the flowering scale or very nearly so. 

 ♦Panicle thick, dense, its branches crowded. 



Flowering scale dull, papery when mature, often finely transversely 

 rugose : plants usually less than 1.5 m. tall. 

 Panicle usually 1 cm. thick or less : bristles commonly green : spike- 

 lets about '2mm. long. 8. C. riridi!^. 



