330 CONTRIBUTIONS FEOM THE NATIONAL HEEBAEIUM. 



examined. The culms and blades are minutely pubescent, the latter 8 cm. long 

 and 12 mm. wide. The spikelets are glabrous and 3 mm. long, the first glume obtuse, 

 3-nerved, nearly as long as the spikelet, the second glume 5-nerved, the sterile lemma 

 2-nerved, the central nerve being suppressed. 



Panicum densum Muhl. Descr. Gram. 122. 1817. No locality is given. The type is 

 not in the Muhlenberg Herbarium. The description suggests one of the Lanuginosa. 



Panicum dichotomum curvatum Torr. Fl. North. & Mid. U. S. 145. 1824. No locality 

 is given. There is no specimen thus marked in the Torrey Herbarium. The refer- 

 ence to tall culms and curved branches suggests P. yadhinense Ashe. 



Panicum dichotomum gracile Torr. Fl. North. & Mid. U. S. 145. 1824. ''Common 

 in swamps, New- York." The type is not in the Torrey Herbarium and the form can 

 not be certainly identified, but the description, "culm tall, slender; leaves mem- 

 branaceous. Common in swamps," suggests the vernal form of P. lucidum Ashe. 



Panicum dichotomum spathaceum Wood, Bot. & Flor. 393. 1874. No locality nor 

 specimen is mentioned and the form can not be identified. 



Panicum disciferum Fourn. Mex. PI. 2: 19. 1886. "San Luis de Potosi (Virl[et] 

 n. 1292)." We have been unable to find the type of this. The name was mentioned 

 earlier, without description, by Hemsley. a The description of the inflorescence as 

 consisting of six appressed spikes suggest that this may not be a true Panicum. 



Panicum discolor Spreng. Mant. Fl. Hal. 31. 1807. The only specimen mentioned 

 is " E Pensylvania. ' ' We have not been able to locate the type and the species can not 

 be identified from the description, though it belongs to the subgenus Dichanthelium. 



Panicum elliottii Spreng.; Steud. Norn. Bot. ed. 2. 2 : 256. 1841, not Trin. 1829. 

 This is given as a synonym of P. pubescens. As the latter name is given without an 

 author, Sprengel's name can be fixed upon no definite species and is hence a nomen 

 nudum. No type has been seen. 



Panicum fir mandum Steud. Syn. PL Glum. 1 : 418. 1854. "Carolina sptr." This 

 was received from M. A. Curtis under the name of P. microcarpon Muhl. We have not 

 seen the type. The description applies well to P. sphaerocarpon except that the 

 spikelets are said to be glabrous while in the latter species they are finely puberulent. 



Panicum fiexuosum Raf.; Desv. Journ. de Bot. 4 : 273. 1814, not Retz. 1791. The 

 description is as follows: "feuilles lanceolees, elatees, ciliees a la base; panicule 

 pubescente; pedoncules flexueux; glume ciliee. Dans le nouveau Jersey." 



Panicum gracilescens Desv.; Poir. in Lam. Encycl. Suppl. 4: 279. 1816. "Cette 

 plante croit a la Caroline (V. s. in herb. Desv.)." The type could not be found in the 

 Desvaux Herbarium and the species can not be identified. Desvaux gives a later 

 description^ which disagrees in some respects with that of Poiret. 



Panicum hirsutum Vahl; Griseb. Fl. Brit. W. Ind. 548. 1864, not Swartz, 1797. This 

 is mentioned as a synonym under P. diffusum Swartz. We have not seen the type but 

 the specific name and the statement by Grisebach that the sheaths of P. diffusum may 

 be glabrous or pilose, suggest that P. hirsutum Vahl may be P. ghiesbreghtii Fourn. 



Panicum iowense Ashe, N. C. Agr. Exp. Sta. Bull. 175 : 115. 1900. "Dry prairies, 

 eastern Iowa to Kansas, June and July." There is no specimen in Ashe's herbarium 

 bearing this name nor that can with any degree of certainty be connected with the 

 description. There is a specimen of P. praecocius collected on dry prairies at Arm- 

 strong, Iowa, July, 1890, by R. I. Cratty, which is marked in pencil by Ashe, "Pani- 

 cum prairie." The description applies fairly well to this specimen except that the 

 height is given as "1-2 cm." [error for 1 to 2 dm.?], the panicle as "small, 1-2 cm. 

 long," and the length of the spikelets as "1.1-1.4 mm." [the spikelets are 1.8 to 1.9 

 mm. long]. The description is too meagre to distinguish this species from P. hua- 

 chucae which is found in the range given, and to which the description of panicles and 

 spikelets better applies. A specimen of P. praecocius, Carver 258, Jewell Junction, 

 Iowa, in the Iowa Agricultural College Herbarium, is marked in Ashe's writing 

 "Panicum haemocarpon Ashe sp. nov. affine P. villosissimum Nash." This adds 

 to the evidence against taking the Cratty specimen as the type of P. iowense. 



a Biol. Centr. Amer. Bot. 3 : 488. 1885. & Opusc. 95. 1831. 



