36 GRAMINEAE. 



Tribe 1. Andropogoneae. Sorghum Tribe. 

 Inflorescence a simple or compound panicle, the ultimate branches of which 

 consist of spikelike racemes of few or many spikelets. Eachis usually jointed 

 at the nodes. Spikelets in pairs at each node, or in triplets at the end of 

 each raceme, of two kinds, one of each pair sessile and perfect or polygamous, 

 the other pedicellate and imperfect, rudimentary, or reduced to the pedicel; 

 pedicel and callus often clot lied with long silky hairs; spikelets generally with 

 but one flower, usually with a hyaline empty bractlet below it, or rarely the lat- 

 ter bearing a staminate flower in its axil, or obsolete. Lower bract always more 

 indurated than the bractlets, the latter often hyaline and usually one of them 

 bearing a bent or twisted awn; internodes between the different bractlets or 

 dowers not measurable. Palea usually shorter than its bractlet, sometimes 

 obsolete. Stamens usually 3, rarely only 2 or 1. 



1. ANDROPOGON L. Sorghum. 



Our only species belongs to the sub-genus Sorghum, having the stems hard 

 and pithy; racemes solitary or in pairs, panicled; joints of the rachis without 

 a translucent line; bracts broad-lanceolate, finally indurated and shining; 

 awnless (in our species) ; lower bractlet empty, or sometimes obsolete, much 

 the smaller, hyaline; upper very slender, awnless or with a geniculate awn; 

 palea small, hyaline or obsolete. Scales wedge-shaped. Stamens 3. Styles 

 distinct. (Greek andro, man, pogon, beard, having reference to the bearded 

 callus of the staminate spikelets in most species.) 



1. A. sorghum Brot. var. halepensis Hackel. Johxsox-grass. Peren- 

 nial, rootstock stout, creeping; stems stout, erect, 2 to 5 ft. high; leaf -blades 

 flat, with undulate margins, 8 to 24 in. long, 1V> to 3 in. wide, apex drooping; 

 panicle variable y 2 to 1% ft. long, oblong-elliptical, dense or rather loose, more 

 or less drooping; branches mostly in whorls of 4, rarely 2 or 6; sessile spikelets 

 variable, lanceolate or elliptical, 2 to 3 lines long; bracts equal; lower bract 

 of the perfect spikelet firm, more or less shining and often dark colored, 

 obscurely 5 to 9 or 11-nerved; margins involute; upper 3 to 7-nerved; bracts 

 of the staminate spikelets narrow and more acuminate, the lower almost 

 2-keeled, with 2 prominent nerves near each margin; upper 5-nerved; empty 

 bractlet one-fourth shorter than the lower bract, elliptical-oblong or oval, deli- 

 cately 2-nerved; lower flower-enclosing bractlet one-half as long as the upper 

 bract, broadly oval, obtuse, 2-lobed, often bearing a short awn; anthers yellow, 

 1 to \y>± lines long; scales fringed; pedicellate spikelets sometimes reduced to 

 the bractlet. much narrower than the fertile ones. — (Sorghum halepense Pers.) 



Originally introduced into the United States as a forage plant, now a 

 troublesome weed in orchards and elsewhere. Sparingly naturalized in the 

 San Joaquin Valley. July-Aug. The rootstocks furnish feed for hogs. 



Tribe 2. Paniceae. Millet Tribe. 



Spikelets arranged in spikes, racemes or panicles, these sometimes digitate 

 or in pairs; rachis usually not jointed :it the nodes and therefore not breaking 

 up nt maturity; pedicels jointed below the bracts so that these fall away 

 with the reel of the Bpikelel ;it maturity. Spikelets terete or flattened on the 

 back <nily, not ;it nil laterally compressed, nil alike, either strictly 1 -flowered, or 



with 1 perfeel flower, and a Btaminate Hewer, or bractlel and palea, or empty 

 bractlet, below it; lower bracl usually much the smaller; perfect flower 

 strictly terminal, its bractlel and palea alike, cartilaginous, coriaceous, char- 



