258 GRAMlNEJi:. J'unicam. 



2. PANICUM, Linn. Panic-Ouass. 



Panicle various, either loose and spreading or close and spike-like, sometimes with 



tlie inflorescence crowded upon one side of a narrow rhachis. Spikelets without 



involucre or bristles at base, 1 1- or 2-flo\vered, articulated with tlieir pedicels. Glumes 



two, herbaceous, the lower smaller, often minute and sometimes wanting, the upper 



equalling the perfect floret. Lower floret stamiuate or neutral, often reduced to a 



single (lower) palet resembling the upper glume ; its upper palet, when present, very 



thin auil hyaline : upper floret coriaceous or cartilaginous, usually closed and mostly 



flattened parallel with the glumes, awnless ; lower palet enclosing the upper. [Scales 



2, fleshy, truncate. Ovary smooth, oblong : stigmas usually purple and longer than 



the styles. Grain compressed, plano-convex, inclosed in the hardened palets. 



A vast largely tro]iical genus, over 800 sjiucies being reconled, of wliicli it is estimated that 

 some 500 are really (iistinct. Tlie Horn of C'aiilbrnia ditlers lemarkalily from tliat of tlie Atlantic 

 States in the small number of native Panieums, as, while 35 to 40 s[)ecies aie found on the easteiii 

 coast, not more than four can be regarded as natives of the western. lUit few of the genus are 

 useful to man ; the couiuion Millet, P. inilinccum, was formerly more cultivated than at present, 

 both for its seeds and as a forage crop. Some botanists arrange the siiecies here enumerated in 

 three dilferent genera, as indicated by the following sections. 



§ 1. Sjnhehts in pairs, one sessile, the other pedirclled, croivded on one side of 

 simjjle fattened branches, which are digitatebj clustered at the toj) of the 

 culia : loicer floret neutral, of a siufjle palet. — DioriAUiA. 



1. P. sanguinale, Linn. (Crab-Ghass or Finger-Grass.) Culms 1 to 2 feet 

 long, usually spreading and creeping at base, then ascending or erect : leaves and 

 sheaths smooth or hairy : spikes four to six or more, 2 io 4 inches long ; s[)ikelets 

 1 to 1^ lines long: lower glume very minute, the upper glume lialf the length of 

 the floret. — Torr. Fl. oS'. York, ii. 423, t. 146. Dic/itaria saiijninalis, Scop.; 

 lieichenb. Icon. Fl. Germ. i. G8, t. 187. P. fmbriatum, Presl in IJel. ILenk. i. 298. 



Introduced; a common annual weed in most countries, apiiearing late in the season and by 

 means of the roots at the lower nodes taking such a iirm hold of the soil as to be very diliicult to 

 remove. The spikes, and sometimes more or less of the plant, are purple. This is undoubtedly 

 the plant collected by Haenke. In the Soutliern States it is miuh valued for both hay and pas- 

 turage. It makes a very light hay, but affords a much-e»teenied pasturage in midsummer. 



P. glabrum, Linn., the Smooth Crab-grass, of Europe and Asia, is very common in tlie Atlan- 

 tic States and is likely to be found here as a weed. It may be distingui.-hed by having its ujiper 

 glume as long as tlie floret, while the spikes are sliorter, fewer, and less regularly digitate. 



§ 2. Spikelets dis/)oscd in jninicles, scattered, awnless. — Panicum proper. 



* Panicle elonyated, racemose: spikelets small, short-pedicelled. 



2. P. agrostoides, Spreng. Culm from a ])erennial root, erctct, abcMit 2 feet 

 high, more or less flattened : leaves long and with the sheaths smooth : i)anicle 

 pyramidal, 4 to 8 inches long, often onesided and freciuently piu-plish ; spikelets 

 crowded and one-sided upon the branches, aboiit a line long, ovate, acute : lower 

 glume half the length of the neutral fl(jret ; tip])er glume 5-ncrved : perfect floret 

 shorter than the upper glume, smooth except a few minute hairs at the apex. — Triu. 

 Spec. Gram, iii, t. 2G1 ; Torr. Fl. N. York, ii. 429, t. 148. 



This, whicli is a common species in the Atlantic States, is given as a native from its occurrence 

 in the collection made by Dr. Pickcruuj and labelled " Valley of the Sacramento." 



-^ Panicle diffuse and spreading. 



■i- Spikelets jiointed. 



3. P. capillare, Linn. (Old-Witch Grass.) Cidnis ot'ten brandling at ])ase 

 and forming large tufts 1 to 2 feet high, frmn an annual root: slicaths, and usually 

 the leaves, very hairy : panicle half the length- of the culm, very open, its long 



