110 Chase — Notes on Genera of Panicece. TV. 



be synonymous with the first, and four new ones, T. recalva, T. tenuis, 

 T. velutina and T. ferruginea. 



Since the notes on Valota were published* Prof. A. S. Hitchcock has 

 examined the types of T. tenuis and T. recalva in Nees' herbarium at 

 Munich, and duplicate types of T. ferruginea and T. velutina in the 

 Trinius Herbarium. Trichachne recalvais seen to be allied to V. Pittieri 

 ( Hack. ) Chase, while T. ferruginea and T. velutina approach Syntherisma 

 through S. adusta. Trichachne tenuis Nees, upon which Kunth based 

 Panicum tenerrimum (Rev. Gram. 1:39. 1.S20) is most nearly allied to 

 V. insidaris, but has much smaller spikelets with less copious and 

 shorter hairs. None of these species are the one referred to t as repre- 

 sented in American herbaria by Nealley's Texas collections and passing 

 under the name of Panicum tenerrimum Kunth. This very distinct 

 species was collected in the summer of 1910 by Prof. A. S. Hitchcock, 

 and is described below : 



Valota Hitchcockii sp. no v. 



Plants perennial, in dense clumps; culms erect, very slender, 30 to 50 

 cm. high, sparingly branching from the lower nodes, glabrous, usually 

 very leafy, the lower nodes ascending-villous, the upper glabrous; sheaths 

 about as long as the internodes or overlapping, the lower silky-villous, 

 the middle and upper with a few, scattered, delicate hairs or glabrous or 

 silky-ciliate only; ligule membranaceous, scarcely 0.5 mm. long, con- 

 tinued as a brown scarious margin down the sheath ; blades ascending or 

 erect, flat, 2 to 4.5 cm. long, 2 to 2.5 mm. wide, scarcely narrowed to the 

 base, glabrous on the lower surface, minutely puberulent or glabrous on 

 the upper, usually with a few long hairs near the base, and with a thin, 

 white, cartilaginous margin; panicles consisting of few to several ascend- 

 ing racemes rather distant along a slender, glabrous axis, the rachises 

 slender, 3-angled, the spikelets mostly in pairs, one short-pediceled, the 

 other on a pedicel about as long as the lower spikelet, thus forming 

 slender racemes, the spikelets scarcely imbricated; spikelets whitish or 

 purplish, 2.5 to nearly 3 mm. long, 0.7 mm. wide, or with the hairs 

 expanded about 1.2 mm. wide; first glume less than A the length of the 

 spikelet, obtuse, glabrous; second glume and sterile lemma equal, 

 strongly 7- to 9-nerved, the internerves and margins densely silky hairy, 

 the hairs at first appressed, at maturity spreading and matted, the spike- 

 lets often matted together by the tangled hairs; fruit 2.1 to 2.2 mm. long, 

 0.6 mm. wide, abruptly short-acuminate, brown, the broad, white, hya- 

 line margins of the lemma nearly covering the palea except at the base. 



Type collected June 24, 1910, on dry prairie soil, San Antonio, Texas, 

 by A. S. Hitchcock (no. 5329). 



Valota Hitchcockii is most nearly related to P. saccharata (Buckl.) 

 Chase, from which it is distinguished by its lower stature, short blades, 

 short racemes of smaller spikelets, the sterile lemma densely hairy on all 

 the internerves, while in V. saccharata the middle four internerves are 



*Proc. Biol. Soc. Wash., 19:186. 1906. 

 + Op. cit. p. 188. 



