2 Chase — Notes on Genera of Panicese. II. 



and was found to be a congener of Sacciolepis striata (L.) Nash., Pan- 

 icum indicum, and allied species. 



Beauvois emphasizes the simple spike-like panicle, and also the real 

 distinguishing character of the genus, the membranaceous lemma and 

 palea, to which latter character the name refers, " De v^v" Membrana; 

 " &x "V Palea . ' ' But, probably because he did not know Lamarck' s species, 

 Beauvois included in Hymenachne P. myuros which does not have a mem- 

 branaceous lemma and palea. Subsequent authors have placed in the 

 genus or section Hymenachne various Panicum allies having a spike-like 

 panicle, but often without other similarity. It is not evident whether 

 Beauvois considered the two species he cites synonymous or not. In the 

 index only Hymenachne myuros is given; A. monostachya is not formally 

 transferred and is not mentioned in the index. 



Roemer & Schultes (1817, Ryst. 2: 25) maintain this and others of Beau- 

 vois' new genera without comment. 



Trinius (1820, Fund. Agros. 176) upholds Hymenachne as a genus with 

 one species, myurus, though Digitaria, Monachne and other genera are 

 included in Panicum. Trinius adds the note: " Obs. Panicis maxime 

 affinis. An hujus generis (forte tunc emendandi) Andropogon insu- 

 laris L. ? " which seems to indicate that he gave greater weight to the 

 membranaceous fruit than to the spike-like panicle. This is assuming 

 that Trinius supposed H. myurus and A. monostachya to be synonyms. 

 Later (1826. Gram. Pan. 51) Trinius places Hymenachne together with 

 Trichachne, Setaria, Permisetum and other genera in Panicum under the 

 following synoptical division "e) Thyrsus (simplex vel compositus ) , aut 

 Racemi compositi longe plerumque sparsi et jubati. Spiculte oblongte 1. 

 lanceolate, pi. min. imequaliter disposita?. Gluma inferior manifesta 

 (Jubaria).*)" ["*Species quarum radii, quantumvis racemos mentientes, 

 radiolos, distinctos emittunt, ad sectionem sequentem Miliariam referun- 

 tur."] This gives a wholly artificial grouping based solely on the narrow 

 panicle and includes ChietocJiloas, various true Panicums and allies. 

 Jubaria (1. c. p. 159-183) is subdivided into four groups, the third of 

 which, "* * * Thyrsi pi. min. compositi spiculsebasi nudse (absque in- 

 volucello)" includes Pan/rum indicum L., P. vilvoides Trin., P. gibbum 

 Ell. (which belong in Sacciolepis), and P. amplexicaule Rudge (true Hy- 

 menachne) under which Hymenachne myuros Beauv. and Panicum myu- 

 ros Kunth "(nee Lam.)" are given as synonyms. Trinius observes 

 " Laniarckii gramen, cui ' folia angusta, convolute' certe hue non per- 

 tinet." But Panicum myuros Lam. and P. amplexicaule continued to be 

 considered synonymous by other authors. Under his fourth division of 

 Jubaria Trinius includes Panicum palustre Trin. (a true Hymenachne 

 having a racemose panicle) between Panicum leucophseum Kunth (which 

 is Valota) and P. plicatum Lam., which belongs in section PtycophyUum 

 of Panicum. These details are given only to show that the cause of con- 

 fusion was the form of the inflorescence. 



Nees (1829, Agros. Bras. 273) recognizes Hymenachne as a genus, but 

 like Trinius groups with it the allies of Panicum gibbum Ell., though he 

 places the following observation after them: " Hac in specie ac in praece- 



