i06 CLXI. GRAMINE^. Setari^. 



12. P. DICHOTOMUM. 



SL much branched and dichotomous above, erect or decumbent, 1— 2f 

 high, branches fasciculate; Ivs. linear-lanceolate, smooth, very numerous, 1 — 2' 

 long' ciliate at base ; panicles lateral and terminal, simple, capillary, with loose, 

 spreading branches ; spikcMs minute, ovoid-obtuse. — Varies with the stem very 

 tall, or low, and decumbent; rather rigid or very slender. N. Eng. to Ky. July. 



13. P. NiTiDUM. Lam. (P. discolor. Muhl.} 



St. erect, slender, 8 — 24' high, the nodes with a ring of dense, deflexed 

 hairs; lis. lance-linear, narrow, acuminate, rather remote, 2 — 4' by 2 — 4"; 

 s/i£at/is as long as the leaves, hairy at the throat and often all over ; stip. ; pan- 

 ick rather small, exserted, roundish-ovoid, diffuse, nearly glabrous, branches 

 spreading; spi.kelets purplish, numerous, small (J" long), oblong, obtuse ; lower 

 glume minute ; abortive fi. neutral, its outer palea equaling the upper glume ; § 

 white, polished. — ^.l Woods and fields, U. S. June. 



a. Tall, simple, smooth, except the densely bearded nodes. — Middle and 

 Western States. 



fi. St. with short branches ; Ivs. and sheaths pubescent. — N. Eng. and Middle 

 States, common. 



y. Low, branched, very hairy, purplish. — Dry fields, N. Eng., common. — 

 These are the extreme fonns, between which there are many intermediate ones. 



14. P. MicROCARPON. Muhl. Darl. 



St. 18 — 30' high, erect, simple, glabrous; joints glabrous; Ivs. lanceolate, 

 veined, ciliate at base, undulate and scabrous on the margin, scabrous above, 

 smooth beneath, 6 — 10"Avide; sheaths deeply striate, smooth ; stip. 0; panicle 

 large, much branched, nearly smooth ; spikelets small, numerous, scarcely pu- 

 bescent; 5 flower as long as the upper glume; //•. .shining, bluish-white. — % 

 Woods and low grounds, Penn. Darlington. 



15. P. CAPiLLARE. Annual Field Panic. 



St. nearly simple, assurgent and thick at base, 1 — ^2f high ; lis. hairy, 

 broad-linear, acuminate, 4 — 6' long ; s/ieaths covered with hispid hairs ; panicle 

 large, pyramidal, capillary, loose, expanding; spikelets small, purple, lanceo- 

 late, acuminate, smooth, on long, hispid peduncles ; abortive Jl. of 1 palea. — 

 Fields and roadsides, U. S. Aug. 

 p. sylvaticnm. Torr. St. very slender, branched at the base. — Woods. 



16. P. vERRUcosLM. Muhl. (P. deWlis. Ell.) 



St. slender, decumbent and geniculate, branching from the base, 1 — 2f 

 high ; Ivs. linear, a few inches long, spreading, smooth ; panicle much expand- 

 ed, few-flowered, flovv^ers verrucose ; abortive flower of one palea, and neuter. — 

 (T)'? Swamps and thickets. Mid. and S. States. Panicle terminal and lateral, 

 loose and capillary. Aug. 



17. P. viRGATUM. Salt-lick Panic. 



Glabrous and often purple ; st. 3 — 5f high ; Ivs. long, linear-lanceolate, 

 hairy at base ; sheaths striate ; stip. with long, white cilice ; panicle virgate, at 

 length spreading, diffuse, very large ; fls. acuminate, and with the glumes, 

 divaricate, palese of the abortive flower nearly equal, enfolding the purple sta- 

 mens. — % Salt-lick prairies, fields, &c., N. Y. to Ind. ! Aug. — None of these 

 species are of much value in agriculture. 



22. SET ARIA. Palis. 



Lat. seta, a bristle ; from the bristly involucres of the spikelets. 



Inflorescence a compound, cylindrical spike ; spikelets 2-flowered, 

 invested with an involucre of 2 or more bristles ; glumes, flowers, 

 paleas and fruit as in the genus Panicum. 



1. S. viRiDis. Palis. Wild Timothy. 



St. smooth, 2 — 3f high; Irs. lanceolate, flat, minutely serrulate; slieaths 

 striate, hairy on the margin, and with a seto.se stipule ; spike cylindric, com- 

 pound, terminal, green; involucre of 4 — 10 fasciculate bristles, much longer 

 than the spikelets; pcdccB of the perfect flower longitudinally striate, punctate, — 

 (J) Common in cultivated "grounds," Free States. July, Aug. 



