150 PANICACE^. 



furrow on each side, 7 mm. long, besides the barbed points at the 

 base and the awns above ; awns 10-20 mm. long, first and second 

 glumes 7-nerved (3 nerves near the middle and 2 toward each edge) ; 

 third glume (floral glume of the rudimentary floret) delicately 5- 

 nerved; fertile floret rough, elliptical, 5-6 mm. long, terminating 

 in a short spine, the floral glume 5-nerved. 



Mexico, Palmer 619, Fringle 2331. 



30. (12) Cham^eraphis E. Br. Prod. 1 : 193 (1810). Setaria 

 Beauv. Agrost. 113 (1812), not Ach. (1798). 



Spikelets with one terminal perfect flower, and a staminate or 

 neuter one below it, crowded into a cylindrical dense or sometimes 

 interrupted spikelike panicle, awnless, articulate with the pedicel, 

 some or all of which bear 1 to several persistent, awnlike, barren 

 branches ; first outer glume small, second larger, floral glume of the 

 barren floret equalling the second or longer, all three membranous; 

 floral glume of the fertile floret firm. Stamens 3. Styles distinct. 

 Grain enclosed, but not adherent. Annual grasses with flat leaf- 

 blades. Panicle terminal. 



Species very variable, about 35, though Bentham said, in Gen- 

 era Plantarum, "Hardly more than 10 that are well deflned." Ex- 

 tensively distributed over the warmer and temperate regions of the 

 globe. Most of them are considered weeds, though the young 

 plant and the seeds make wholesome food for many domestic ani- 

 mals. 



The older authors included C hanueraphis {Setaria) in Pani- 

 cum, and it has been restored as a section by Studel and Doel. It 

 is easily recognized by the dense spikelike panicle, usually bristling 

 with numerous setae issuing from the pedicels below the spikelets. 

 The setffi are not epidermal, like the hairs of many plants, but are 

 thought to represent abortive branchlets inserted helow the articula- 

 tion of the pedicels. A few species have the lower flower perfect as 

 well as the upper, which is quite exceptional in Panicece. Panicum 

 unisetum Trin. has a single awn on some of the pedicels, and on this 

 account has been by some called Setaria tiniseta, while Presl called 

 it Urochloa uuiseta, and Schlecht founded a genus for it called Ix- 

 ophorus. 



