GENERA OF GRASSES OF THE UNITED STATES. 245 



Fruit pale (yellowish to straw or light brown). 

 Bristles green. 



Panicle more or less open-lobulate stramineofructa. 



Panicle dense or slightly lobulate at base germanica. 



Bristles brown or purple. 



Bristles brown brunneoseta. 



Bristles purple. 



Panicle more or less lobulate hostii. 



Panicle dense or slightly lobulate at base metzgeri. 



Subsp. ntbrnfructa Hubb. : The only forms cultivated in the United States 

 are var. pitrpiircoscta Ilubb., Turkish millet, with purple bristles and a large 

 lobulate head; and subvar. violacea (Alef.) Hubb., Kursk millet or Siberian 

 millet, with purple bristles and a smaller dense head. 



Subsp. niyrofructa Hubb. : The common form cultivated in the United States 

 is var. atra, or Hungarian grass. This has small dense heads 1 to 3 inches long 

 with purple bristles. 



Subsp. stramineofructa Hubb., German millet: Plants robust with heads 4 

 to 12 inches long and as much as 2 inches wide, the bristles noticeably longer 

 than tbo spikolots. Forma breviseta (Doell) Hubb., Golden Wonder millet, 

 differs in having bristles shorter than the spikelets or barely exceeding them. 



Subsp. germanica (Mill.) Hubb., common millet: Heads mostly 2 to 3 inches 

 long, one-fourth to one-half an inch thick, the bristles noticeably longer than 

 the spikelets; forma mitis (Alef.) Hubb. with bristles shorter than the spike- 

 lets or barely exceeding them. There has been an unfortunate misapplication 

 of the name German millet. The forms cultivated under this name are not 

 the subspecies germanica as one would suppose (see the preceding subspecies). 

 Var. bfunneoseta Hubb., Aino millet : Head large, lobulate, brown. Subvar. 

 densior Hubb. has a compact scarcely lobulate head. 



Var. hostii Hubb., German millet : Head large, lobulate, purple ; differs from 

 the other form of German millet (subsp. stramineofructa) in having purple 

 bristles. 



Var. metzgeri (Kornicke) Hubb., common millet: Bristles noticeably longer 

 than the spikelets; differs from the other form of common millet (subsp. ger- 

 manica'] in having purple bristles; sometimes called Hungarian grass, a name 

 which should be applied to subsp. nigrofructa. 



125. PENNISETUM Rich. 



Spikelets solitary or in groups of two or three, surrounded by an 

 involucre of bristles, these not united except at the very base, often 

 plumose, falling attached to the spikelets; first glume shorter than 

 the spikelet, sometimes minute or wanting; second glume shorter 

 than or equaling the sterile lemma; fertile lemma chartaceous, 

 smooth, the margin thin, inclosing the palea. 



Annual or perennial, often branched grasses, with usually flat 

 blades and dense spikelike panicles. Species about 50, in the tropical 

 regions of both hemispheres ; 1 species in southern Florida. 



Type species: Pennisetnm typhoideum Rich. 



Penniseturn Rich., in Pers. Syn. PI. 1 : 72. 1805. Five species are described, 

 1\ typhoideum, P. setosum, P. cenehroides, P. orientale, and P. molaceum. 

 Pennisetum typhoideum, being a well-known economic species, is chosen as the 

 type. 



