144 Chase — Notes on Genera of Panicecs. TV. 



Trinius (Mem. Acad. St. Petersb. VI. Sci. Nat. 3 2 : 195, 320. 1834) 

 makes Ichnanthus (spelling it " Ichnantus " ) a section of Panicum, with 

 the synoptical heading " Flosculus * * * hermaphroditns basi faciei 

 utrinque canalicnlato-scrobiculatns vel (plerumque) auriculato appendicu- 

 latus," thus indicating the group as to-day accepted, including species 

 in which there is a scar or excavation at base as well as those having 

 appendages. 



Steudel (Syn. PI. Glum. 1 : 93. 1854) follows Trinius. 



Bentham (Fl. Hongkong. 41 3. 1861 ) adopts Ichnanthus as a genus in 

 this emended sense, including in it I. pallens (Sw. ) Munro. 



Grisebach (Fl. Brit. W. Ind. 550. 1864) gives it, in the same sense, as 

 a section of Panicum. 



Doell (Mart. Fl. Bras. 2 2 : 276. 1877) maintains Ichnanthus as a 

 genus for the group segregated as Panicum, section Ichnanthus by 

 Trinins, making under it two divisions "I Valvula inferior ad basin 

 utrinque auriculatus" and ' ; II Valvula inferior ad basin utrinque 

 scrobiculata." 



Bentham (Benth. & Hook. Gen. PI. 3 : 1103. 1883) and Hackel ( Engler 

 & Prantl, Pflanzenf. 2 2 : 36. 1887) maintain Ichnanthus as a genus for 

 this larger group. 



(Schultes, Mant. 2 : 281. 1824, misspells the name " Ischnanthus." ) 



Description. — Inflorescence paniculate, the spikelets mostly short- 

 pediceled along the usually sub-simple branches; spikelets more or less 

 laterally compressed, the glumes and sterile lemma strongly nerved; first 

 glume usually more than half the length of the spikelet, broad, acute; 

 second glume and sterile lemma subequal, acute, exceeding the fruit, the 

 lemma enclosing a membranaceous palea and rarely a staminate flower; 

 fruit acute or subacute, indurated, the margins of the lemma usually flat, 

 the rachilla produced below the lemma into a usually minute stipe, this 

 bearing on either side membranaceous appendages adnate to the base of 

 the lemma and free above, the appendages sometimes wanting and indi- 

 cated by minute excavations only. Perennials, usually with lanceolate 

 blades abruptly contracted into a petiole-like base; the genus mostly con- 

 fined to the. tropics of the western hemisphere, one species extending into 

 the Old World. 



Ichnanthus is closely allied to Panicum and appears to be but a loosely 

 coherent genus, several of the species differing from each other almost as 

 much as some of them differ from species of Panicum. A few species, 

 such as /. lanceolatus Scribn., in which the appendages are wholly want- 

 ing and even the scars obscure ( but in which the lemma margins are 

 flat), are nearly as referable to one genus as to the other. 



19. Genus LASIACIS (Griseb.) Hitchc. 



Lasiacis Hitchc. Contr. Nat Herb. 15 : 16. 1910. "The type of the 

 genus is Lasiacis divaricata (L. ) Hitchc, based on Panicum diraricatum 



