GEAMINEiE. (GBASS FAMILY.) 575 



oblong-obovato acute spikelets near the summit ; glumes papillose-hispid, the 

 upper one 5-nerved, longer than the pointed granular-roughened perfect flower ; 

 the lower minute, obtuse. — Dry soil, Florida to South Carolina. — Culms 1°- 

 2° long. Spikelets Ij" long. 



* * * Spikelets single, on a spreading pedicel, dhposed in open panicles : sterile flower 

 consisting of two unequal palece, neutral (except No. 17) : perennials: culms at 

 length much branched. 



17. P. latifolium, L. Culms smooth, erect ; leaves ovate-lanceolate, 

 mostly smooth, the sheaths, especially at the joints, villous ; panicle nearly sim- 

 ple; spikelets large (2" long), obovate; glumes pubescent, obtuse, the upper 

 2-3 times longer than the lower one ; sterile flower 3-androus. — Dry rich soil, 

 Florida, and northward. May. — Culms 1° - 1^° high. Leaves and panicles 

 3' -4' long, the latter exserted. 



18. P. clandestinum, L. Culms rigid (1° high), branched, naked at 

 the joints ; leaves lanceolate, acuminate, the sheaths papillose-hirsute ; panicles 

 small, lateral and terminal, more or less included in the sheaths ; spikelets ob- 

 long, pubescent (1^" long) ; lower glume half the length of the 7-nerved upper 

 one. — Dry sterile soil. North Carolina, and northward. Sept. IJ. — Varies 

 with the sheaths smooth, or merely pubescent, and the terminal panicle some- 

 times exserted. 



19. P. SCOparium, L. Hairy or woolly all over, except the upper sur- 

 face of the somewhat rigid lanceolate leaves ; culms stout (1° - 1 J° high), mostly 

 siraple; panicle terminal, exserted; spikelets obovate (1^" long), obtuse, pubes- 

 cent ; upper glume 9-nerved, three times the length of the lower one ; sterile 

 flower neutral. — Open woods and margins of fields, in dry soil, Florida to 

 North Carolina. May. 



20. P. pauciflorum, Ell. "Panicle expanding, few-flowered; flowers 

 very large ; leaves narrow-lanceolate, ciliate at the base ; sheaths hairy." Ell. — 

 In close damp soils, Georgia, Elliott. May. — Culm 12' -18' high, roughish 

 and branching at the joints. Leaves 3' - 4' long, 3" - 4" wide, smooth above. 

 Spikelets oval, the lower glume very small. Resembles P. scoparium in fruit, 

 and P. villosum somewhat in habit. ( *) 



21. P. divarieatum, L. Shrubby, smooth; culms reclining, with short 

 and spreading branches ; leaves lanceolate, faintly nerved, deciduous from the 

 persistent sheaths ; panicles small, simple, few-flowered, terminating the branches ; 

 spikelets (2" long) obovate, tumid, nodding ; glumes smooth, many-nerved, and, 

 like the lower palea of the sterile flower, tipped with a tuft of down ; paleae of 

 the sterile flower nearly equal. — South Florida, Dr. Blodgett. — Leaves lJ'-2' 

 long. Branches of the panicle short and diverging. 



22. P. viscidum, Ell. Soft-hairy or downy all over, except a narrow ring 

 below each joint of the culm ; leaves lanceolate ; sheaths viscid ; panicle (4' -6' 

 long) compound, diffuse; spikelets (1" long) ovate, pubescent; upper glume 

 9-nei'ved, many times longer than the minute lower one. — Varies with the 

 leaves, sheaths, and purple spikelets smooth. — Wet swamps and bogs, near the 



