HITCHCOCK AND CHASE NOETH AMEEICAN PANICUM. 



139 



80. Panicum rudgei Roem. & Schult.« 



Bras. 48. 1823. "Species rarissima 



Panicum, scoparium Rudge, PL Guian. 1 : 21. pi. 29. 1805, not Lam. 1798. No par- 

 ticular locality in Guiana is mentioned by Rudge. In the Berlin Herbarium is a 

 specimen from Rudge which is authentic though it probably is not the type. The 

 original description and the plate leave no doubt as to the identity of the species. 



Panicum rudgei Roem. & Schult. Syst. Veg. 2: 444. 1817. Based on "Pan. 

 scoparium Rudge. " 



Panicum rudgei brasiliense Raddi, Agrost. 

 observata tantum in viciniis fluminis Inhu- 

 mirim." We have not seen the type of this, 

 but the description applies to the type of P. 

 rudgei. 



Panicum dasytrichum Spreng. Syst. Veg. 

 1: 317. 1825. "Brasil." The type, in the 

 ^Sprengel Herbarium, was collected by Hoff- 

 mansegg. 



Panicum hirsutum Willd.; Spreng. Syst. 

 Veg. 1: 317. 1825, not Swartz, 1797. This 

 is given as a synonym under P. dasytrichum 

 and is credited to "W. herb." The type, 

 in the Willdenow Herbarium, was collected 

 by Hoffmansegg in Brazil. 



Panicum rhigiophyllum Steud. Syn. PL 

 Glum. 1: 76. 1854. "P.rigens. -SaZzm. Hrbr. Bahia. " This specimen was not found 

 in the Steudel Herbarium, but a Salzmann specimen bearing this name was examined 

 at Halle. 



Fig. 133.— p. rudgei. From Salzmann's 

 specimen of P. rigens. 



o- The following species, though not North American, may here be described on 

 account of its relationship to Panicum rudgei: 



Pamcum rotimdum sp. nov. = w *i3=Ns-\ tV-W^ 



Plants perennial, in small tufts; culms 30 to 50 cm. high, rather stout, stiff, erect or 

 somewhat geniculate at base, densely ascending-hirsute, the nodes densely bearded; 

 sheaths, except the upper, mostly shorter than the internodes, hirsute like the culms; 

 ligules membranaceous, ciliate, the hairs mingling with those of the blade ; blades thick, 

 erect or appressed, linear, 5 to 20 cm. long, 2 to 5 mm. wide, more or less involute, at 

 least toward the long-acuminate apex, only as wide as the sheath at base, the juncture 



obscure, densely hirsute on the upper surface, 

 harshly velvety beneath; panicles terminal and in 

 the axils of the upper 1 to 3 leaves, forming an oblong 

 inflorescence as in P. rudgei, about one-third the 

 height of the plant, the main axis pilose, the slender, 

 angled, scabrous, stiff but flexuous branchlets as- 

 cending or spreading, pilose in the axils, the long 

 pedicels divergent; spikelets2.3 to 2.5 mm. long, 1 

 to 1.2 mm', wide, very turgid, abruptly pointed, 

 strongly nerved, a few stiff, appressed hairs here 

 and there between the nerves; first glume over half 

 the length of the spikelet, abruptly pointed; sec- 

 ond glume and sterile lemma subequal, exceeding the fruit, the lemma subtending 

 a palea and staminate flower; fruit 1.8 mm. long, 1 mm. wide, ellipsoid, smooth and 

 shining, a broad scar at the base. 



Fig. 134.— p. rotunduvi. 

 type specimen. 



From 



