36 CONTRIBUTIONS FEOM THE NATIONAL HERBARIUM. 



Spikelets 5 to 6 mm. long 15. P. texanum. 



Spikelets 2 to 4 mm. long. 



Spikelets strongly reticulate- veined, 2 to 3 mm. long; 

 glabrous. 

 Panicle branches long and spreading; blades pubes- 

 cent or glabrous 11. P.fasciculatum. 



Panicle branches short, appressed; blades narrow, 



pubescent 11a. P. fasciculatum 



chartaginense. 

 Spikelets scarcely reticulate-veined or only near apex. 



Spikelets not over 2 mm. long, glabrous 10. P. reptans. 



Spikelets over 3 mm. long, pubescent. 



Rachis scabrous but not bristly 13. P. adspersum. 



Rachis pilose with bristly hairs. 



Plant more or less velvety, sheaths not 



papillose 12. P. molle. 



Plant not velvety; sheaths papillose 14. P. arizonicum. 



10. Panicum reptans L. 



Panicum reptans L. Syst. Nat. ed. 10. 2: 870. 1759. No locality is here given, 

 but the same specimen is described more fully by Linnaeus, under the name Panicum 

 grossarium, later in his list of Jamaica plants. « The type specimen, in the Linnsean 

 Herbarium, is marked "Br" [for Browne who sent the plant] and on the sheet the 

 word "reptans" was written and then crossed out. A full discussion of the type of 

 this and P. grossarium is given in another place. 5 



Panicum grossarium L. Syst. Nat. ed. 10. 2 : 871. 1759. The type specimen is the 

 same as that of P. reptans. 



Panicum prostratum Lam. Tabl. Encycl. 1:171. 1791. "Ex Insulis Caribseis." 

 The type, in the Lamarck Herbarium, is from Santo Domingo. 



Panicum caespitosum Swartz, Fl. Ind. Occ. 1: 146. 1797. "Habitat in pascuis 

 siccioribus Jamaicae." The type, c in the Swartz Herbarium, is from "Jamaica, 

 Swartz." 



Panicum insularum Steud. Syn. PI. Glum. 1: 61. 1854. "Ins. Antillae minores." 

 The type, in the Steudel Herbarium, is labeled "Panicum insularum Steud. An- 

 tillae minores. Hohenacker." 



Brachiaria prostrata Griseb. Abh. Ges. Wiss. Gottingen 7:263.1857. Based on 

 Panicum prostratum Lam. 



Panicum aurelianum Hale in Wood, Class-book ed. 3. 787. 1861. "Damp soils, 

 about N. Orleans (Hale)." We have not been able to locate the type of this, but in 

 the herbarium of the Missouri Botanical Garden there is a specimen of P. reptans 

 bearing a ticket reading "Panicum aurelianum New Orleans Dr. Hale." This agrees 

 perfectly with Hale's description. 



Panicum prostratum pilosa[um] Eggers, Fl. St. Croix & Virgin Isl. 104. 1879. "St. 

 Croix (La Grange)." We have not seen the type. The description applies to the 

 common form of P. reptans with pilose rachises. 



a Amoen. Acad. 5 : 392. 1759. 

 & Hitchcock, Contr. Nat. Herb. 12: 119. 1908. 



c For an account of Swartz's American grasses, which are preserved in the Natural 

 History Museum at Stockholm, see Hitchcock, Contr. Nat. Herb. 12: 138. 1908. 



