* 80 POACEAE 



2. Amphicarpon Floridanum Chapm. Stems tufted, from a long stout rootstock, 

 the aerial 3-8 dm. tall, naked above and bearing a terminal contracted panicle 3-23 cm. 

 long, the lanceolate spikelets numerous, 6-7 mm. long ; subterranean stems 3-15 cm. long, 

 scaly at the base, with a single terminal spikelet : leaf-sheaths papillose-hispid at the 

 summit and along the margins, or sometimes the lower ones all over ; blades erect or as- 

 cending, glabrous on both surfaces, or sparingly pubescent above, 2 dm. long or less, 1 

 cm. wide or less, lanceolate. 



In dry sandy soil, Florida. Summer and fall. 



25. ERIOCHLOA H.B.K. 



Perennial grasses, with flat leaf -blades and an inflorescence composed of spike-like one- 

 sided racemes which are racemosely arranged. Spikelets with an annular callus at the 

 base, articulated below the callus, 1-flowered, imbricated, arranged in 2 rows on a flat 

 rachis, acute or acuminate. Scales 3, the two outer membranous, empty, acute or 

 acuminate, the third scale glabrous and shining, shorter, at length indurated, awn-pointed 

 or short-awned at the apex, enclosing a palet of similar texture and a perfect flower. Sta- 

 mens 3. Styles distinct. Stigmas plumose. 



Flowering scale % as long as the spikelet or more, the awn a mere point or apiculation. 

 Hairs at the apex of the pedicels none, or few and short. 



Rachis of the inflorescence and racemes puberulent or with a few scattered 



long hairs. 1. E. longifolia. 



Rachis of the inflorescence and racemes densely pilose with long hairs. 2. E. mollis. 



Hairs at the apex of the pedicels many, more than % as long as the spikelet. 3. E. sericea 



Flowering scale usually about % as long as the spikelet, the awn %-% as long as 



the scale. 4. E. punctata. 



1. Eriochloa longifolia Vasey. Stems tufted, 4-8 dm. tall : leaf -sheaths glabrous ; 

 blades erect or ascending, 4 dm. long or less, 2-4 mm. wide, smooth : inflorescence 6-20- 

 cm. long, its axis puberulent or with a few scattered long hairs : racemes erect, 2-4 cm. 

 long, puberulent : spikelets 8-16, ovate-lanceolate, about 5 mm. long, on puberulent 

 pedicels, the 2 outer scales appressed-pubescent with long hairs, 5-nerved, acute or obtuse ; 

 third scale about 3.5 mm. long, coarsely transverse-rugose, about f as long as the spikelet, 

 apiculate, or with a short awn less than 1 mm. long. 



In sandy soil, southern peninsular Florida. Spring. 



2. Eriochloa mollis (Michx. ) Kunth. Stems single, 7-15 dm. tall, densely and 

 softly pubescent at and near the nodes : leaf -sheaths glabrous or softly pubescent with short 

 ascending hairs ; blades 1-4.5 dm. long, 4-15 mm. wide, smooth and glabrous : inflores- 

 cence 1.5-4 dm. long, its axis densely pilose with somewhat ascending hairs : racemes erect 

 or nearly so, 8-20, 3-15 cm. long, the rachis densely pilose with somewhat ascending hairs : 

 spikelets 12-40, 5-5.5 mm. long, ovate, acute, on pilose pedicels, the 2 outer scales appressed- 

 pubescent with long hairs, 5-nerved, acute ; third scale about 3.5 mm. long, rather finely 

 transverse-rugose, apiculate, or with a very short awn. [Panicum molle Michx.] 



In low pine lands, South Carolina to Florida. Summer. 



3. Eriochloa sericea Munro. Stems tufted, 4-10 dm. tall, softly pubescent at and 

 near the nodes : leaf-sheaths usually softly pubescent ; blades glabrous or pubescent, 4 mm. 

 broad or less, those on the innovations 1-3 dm. long, those on the stem 3-20 cm. long : 

 inflorescence 1-2 dm. long, its axis pubescent with short ascending hairs ; racemes ap- 

 pressed, 5-9, 1-4 cm. long, the rachis pubescent with short ascending hairs : spikelets 

 10-24, 4.5-5.5 mm. long, ovate, acutish, on pedicels which are densely hispid at the apex 

 with hairs more than as long as the spikelet, the 2 outer scales pubescent with rather long 

 hairs, acute or obtuse ; third scale 3-3.5 mm. long, transversely rugose, apiculate. 



In dry soil, Texas and the Indian Territory to New Mexico. Summer. 



4. Eriochloa punctata (L.) Hamilt. Stems tufted, 2-8 dm. tall, finally much 

 branched, the nodes puberulent : leaf-sheaths and blades glabrous or pubescent, the latter 

 2-30 cm. long, 3-10 mm. wide : inflorescence 6-20 cm. long, its axis pubescent with 

 short ascending or nearly appressed hairs : racemes erect or nearly so, 4-20, 1.5-4 cm. 

 long, the rachis with short ascending hairs: spikelets 10-30, 4.5-5.5 mm. long, lanceolate, 

 acuminate, on appressed-pubescent pedicels, the 2 outer scales appressed-pubescent with 

 long hairs, acuminate ; third scale transversely rugose, from -f as long as the spikelet, 

 about 2.5 mm. long, exclusive of the hispid awn which is J as long as the scale or more. 



On plains or prairies, Kansas to Texas. Summer and fall. EVERLASTING GRASS. 



26. BRACHIARIA Ledeb. 



Grasses with flat leaves and the spikelets borne in 2 rows in one-sided spikes. Spikelets 

 of 4 scales, the outer 3 membranous, the fourth scale chartaceous, indurated in fruit, trans- 



