GENERA OF GRASSES OF THE UNITED STATES. 241 



123. TRICHOLAENA Schrad. 



Spikelets on short capillary pedicels; first glume small, much 

 shorter than the spikelet, villous; second glume and sterile lemma 

 equal, raised on a stipe above the first glume, emarginate or slightly 

 lobed, short-awned, covered, except toward the apex, with long silky 

 hairs, the palea of the sterile lemma well developed ; fertile lemma 

 shorter than the spikelet, cartilaginous, smooth, boat shaped, obtuse, 

 the margins thin, not inrolled, inclosing the margins of the palea. 



Perennial or annual grasses, with rather open panicles of silky 

 spikelets. Species about 15, in the Eastern Hemisphere, mostly in 

 Africa, one cultivated in the United States. 



Type species: Tricholaena micrantha Schrad. 



Tricholaena Schrad.; Schult, Mant. 2: 163. 1824. Three species are de- 

 scribed, but the second and third are included in the genus with a question. 

 The first species is taken as the type. 



Tricholaena rosea Nees (fig. 147), Natal grass, is becoming an 

 important forage grass in the sandy lands of Florida, where it has 

 been recently introduced. It is an upright, rather slender perennial, 

 2 to 4 feet tall, with beautiful purple panicles, 4 to 10 inches long. 

 The color varies from. light purple or pink to wine color. Although 

 a perennial, it is usually cultivated as an annual, as it will not survive 

 temperatures below freezing. 



124. CHAETOCHLOA Scribn. 

 (Setaria Beauv.) 



Spikelets subtended by one to several bristles (sterile branchlets), 

 falling free from the bristles, awnless; first glume broad, usually 

 less than half the length of the spikelet, 3 to 5 nerved ; second glume 

 and sterile lemma equal, or the former shorter, several-nerved; fer- 

 tile lemma coriaceous indurate, smooth or rugose. 



Annual or perennial grasses, with narrow terminal panicles, these 

 dense and spikelike or somewhat loose and open. Species about 65, 

 in the tropical and warm temperate regions of both hemispheres; 18 

 species in the United States. 



Type species: Panicum viridc L. 



Setaria Beauv., Ess. Agrost. 51, pi. 13, f. 3, 1812, not Acharius, 1789, nor 

 Michaux, 1803. Fourteen species are listed, 8. viridis being illustrated. Pani- 

 cum viride L., on which this species is based, is taken as the type. 



Chaetochloa Scribn., U. S. Dept. Agr., Div. Agrost. Bull. 4 : 38. 1897. Scribner 

 proposes the name Chaetochloa for Setaria Beauv., stating that the name Setaria 

 was first used by Beauvois (Fl. Owar. 1809) 1 for a species of Pennisetum. 

 Scribner himself applies the name Chaetochloa to the species allied to Panicum 

 viride. Hence it seems that he wished to substitute Chaetochloa for Setaria 

 as used by Beauvois in his Essai (Ess. Agrost. 51, pi. 13, f. 3, 1812). The figured 

 species, Setaria viridis (L.) Beauv., becomes the type. 



The name Ixophorus Schlecht. was applied to this genus by Nash, 2 but that 

 is based on a Mexican species not congeneric with ours. 



1 According to Dr. J. H. Barnhart the part containing Setaria (PI. Owar. 2: 80) was 

 not published until 1818. 



2 Britton and Brown, Illustr. Fl. 1 : 125. 1896. 



97769 19 Bull. 772 16 



