Chase — Notes on Genera of Panicecs. TV. 131 



Lappagopsis Steud. Syn. PI. Glum. 1 :112. 1854. This genus is pro- 

 posed with a single species L. bijuga Steud. " Urville legit in Ins. St. 

 Catharin. et Claussen in Brasil." The Claussen specimen referred to is 

 in the Kew Herbarium. It is found to be closely related to Paspalum 

 dissitiflorum Trim, which species Nees (Agrost. Bras. 32. 1829) includes 

 in his section " Digitariae (speculis inversis)." Hackel (Engler & Prantl. 

 Pflanzenf. 2 : 2 35. 1887, where the name is misspelled " Lappagroslis") 

 includes it in section Anastrophus. 



Owing to its insufficient diagnosis and the diverse species assigned to 

 Anoxopus by Beauvois this name has been applied to different groups of 

 species by different authors. Roemer & Schultes (Syst. Veg. 2 : 318. 

 1817) recognize it as a genus including under it the same species as did 

 Beauvois except A. paniceus which, they say, is Paspalum fili for me [it is 

 a species allied to Syntherisma filiformis] . Nees, as we have seen, used it 

 as a section of Paspalum for the species allied to A. aureus. Hooker (Fl. 

 Brit. Ind. 7 : 61. 1896) says of Axonopus "A natural genus, remarkable 

 for the small cleft palea of gl. Ill [the sterile palea]. It was established 

 by Beauvois on Panicum cimicinum Retz, to which other grasses having 

 no affinity with it were added." Hooker does not state why he takes 

 P. cimicinum as the basis of A[nd,xopus. It fails to agree with one of 

 the two characters of Beauvois' diagnosis (in that its spikelets are not 

 solitary), and it is only third in the list. Hooker here includes one other 

 species in this genus, A. semialatus (based on Panicum xemialatum R. Br. ) 

 Stapf (Dyer, Fl. Cap. 7:418. 1898) accepts the genus as emended by 

 Hooker. Hitchcock (Rhodora 8 : 205. 1906; Contr. Nat. Herb. 12 : 141. 

 1908; Gray, Man. ed. 7. 100. 1908; Contr. Nat. Herb. 12:207. 1909.) 

 recognizes Axonopus for the congeners of A. compressus. 



Description. — Inflorescence of 2 to many slender racemes usually aggre- 

 gated at the summit of the culm; spikelets solitary, sessile and alternate 

 in two rows on one side of a 3-angled rachis, the back of the fertile lemma 

 turned from the axis; spikelets depressed-biconvex, not turgid; first glume 

 wanting; second glume and sterile lemma equal; sterile palea obsolete; 

 fruit indurated, oblong-elliptic, usually obtuse, the margins of the lemma 

 slightly inrolled. Stoloniferous or tufted perennials, with flat, condupli- 

 cate or involute, linear leaves; species numerous in South America, a few 

 species extending into subtropical and warm temperate regions of North 

 America and one or two to the warmer parts of the Old World. 



The characters to which we here attach chief value as generic are the 

 reversed and solitary spikelets (in which the first glume is wanting) and 

 the racemes aggregated at the summit of the culm. 



The genus Axonopus as here understood, subdivides into three rather 

 well-marked sections as follows : 



Rachis and spikelets glabrous or the latter softly pubes- 

 cent, neither bearing conspicuous, stiff, spreading 

 hairs Axonopus proper. 



Rachis and sometimes spikelets bearing conspicuous, stiff, 

 spreading hairs. 



