Phalakis. CLXl. GRAMINEiE. 607 



2. S. GLAUCA. Palis. Dottk Grass. 



SL 2 — 3f high ; Ivs. lanceolate, carinate, rouf^h, hairy at base ; sheaths 



striate, smooih; .s7/;'. setose; spike cylinchic, yellowish-green, 2 — 4' long; inval. 



ot G — 10 (ascick'd, scabrous bristles much longer than the spikeh-ts ; pa/ra of Ihe 



perfect Jl. transversely rugose. — (\) Fields and roadsides, JN. Eng. to (Jhio. Jl. Aug. 



/?. (S. purpurascens. R. tj' S.) SheiUhs and spikekLs pilose. — Penn. 



3. S. VKRTICILLATA. Palis. 



St. smooth, about 2f high; Ivs. lanceolate, rough-edged; sheaths ^\Xioo\\ 

 liairy on the margin ; spicate panicle coniposed of short, divided branches in in- 

 terrupted verticils, 2 — 3' long; bristles of the invol. in pairs, rough backwards; 

 palcie of the ^ roughish punctate,— (I) Sandy fields, N. Eng. to Ohio. July. ^ 



4. S. iTAi.icA. Palis. 



S/. somewhat compressed, about 4f high ; Ivs. lanceolate, I — 2f long, an 

 inch wide; sheaths roughish, pilose at the throat; spi/ce compound, interrupted 

 at the base, nodding, 6 — 8' long ; spikclets conglomerate ; invol. of 2 bristles, 

 several times longer than the flower.— (I) Ditches, Mid. and S. States. July. 



5. S. Gfrmanica. Palis. Millet. Bengal Grass. 



St. 2 4f high, simple, leafy ; Ivs. lance-linear, flat, acuminate, serrulate 



on the margin; sheaths striate, close, pubescent; slip, bearded; spike compress- 

 ed, yellowish, oblong-cvlindric; ra-chis densely hirsute ; involucrate brislks 4 — 8, 

 as'lbng as, or longer than the spikelets, yellowish; glumes unequal, ovate; ^ 

 paleee smooth, obscurely 3-veined.— ® In fields, not often cultivated. ^ 



23. CENCHRUS. 



Gr. KEvypos, millet; this grass bearing some resemblance to the millet. 



Flowers racemose or spicate; involucre burr-forra, laciniate, echi- 

 nate, persistent, including 1 — 3 spikelets ; glumes 2, 2-flowered, outer 

 smaller ; flowers dissimilar, the lower sterile, the upper perfect ; 

 scales 0. 



C. TRiBL'LoiDES. (Also C. ecMnatus Linn. ?) Burr Grass. 

 St. 1 — 2f long, erect or procumbent and geniculate at base ; Ivs. lance- 

 linear, conduplicate, gradually acuminate, 3 — 5' by 2 — 3"; sheaths open, about 

 as long as the colored joints; spike with the burr-like involucres approximate 

 i7ivol. cartilaginous, beset externally with many sharp, retrorsely hispid spines 

 as long as itself and containing 2 — 3 spikelets; glumes acuminate-mucronate, 

 about 3" long, producing but 1 caryopsis. — Q Sandy soils, N. J. 

 Tribe 5. PHAL.AREJE. — Inflorescence a contracted panicle. Spikelets 



solitary, witli 1 perfect flower and 1 — 2 imperfect ones. Lower palea awned 



or mucronate, upper with two keels. 



24. PHALARIS. 



Gr. (pa'Xapos, brilliant; on account of its smooth, shining seeds. 



Spikelets 1 -flowered ; glumes 2, subequal, carinate; paleae 2, 

 coriaceous, awnless, shorter than the glumes, coating the caryopsis, 

 each with an external, accessory palea or abortive rudiment at base. 



1. P. arundin'acea. (P. Americana. Torr.) 



St. erect, sparingly branched or simple, 2 — 5f high ; Ivs. spreading, lanceo- 

 late, veined, rough-edged, on smooth, striate sheaths ; panick oblong, jspicate, 

 somewhat secund, 3—4' long, glumes 3-veined, whitish, scabrous; rudiments 

 pilose. — % Common in ditches "and swamps, Can. to Car. and K}^ A large, 

 showy grass, but not valuable. July, Aug. 



(3 pi eta is the well-known striped or ribbon grass, with beautifully variegated 

 leaves longitudinally striped in endless diversity, f 



2. P Canarienses. Canary Grass. 



St. erect, or geniculate at the lower joints, round, striate, leafy; Ivs. lanceo- 

 late; panicles spicate, ovoid, erect ; glumes whitish, with green veins; rudiments 

 smooth. — d) Fields and pastures, not common. Jl. § 



