The species in this group are much confused and no two botanists have interpreted 

 them alike. The following notes on the several species may be of interest. 

 Panicum fuscum Swartz is apparently the most common and widely distributed 

 species in the group and is represented in the U. S. National Herbarium by 

 specimens from Florida, Texas, New Mexico, Mexico, St. Croix, Porto Rico, 

 Martinique, Honduras, and Costa Rica. It is distinguished jjy its ascending 

 panicle branches, dark-brown, somewhat obtuse, glabrous spikelets, the outer 

 glumes of which are prominently reticulate-veined. See Trin. Icon. 2 : t. 206. 

 1829. The plant figured by Trinius is doubtless P. fasciculatum Sw. which evi- 

 dently is only a large form of P. fnKnnn. 



PANICUM FUSCUM RETICULATUM (Torr. ) Scribn. & Merrill n. comb. (P. 

 recticulatum Torr. in Marcy's Explor. Red R. La. 299. 1853; P. fasciculatum 

 reticulatum Beal, Grasses 'N. A. 2: 117. 1896.) 



Tucson, Nos. 15^5, 1616; Papayo Reservation, No. 1754. 



This variety is distinguished from the species only by its contracted panicles an<l 

 should perhaps be considered only as a form of Pan icum fuscum Sw. It is rep- 

 resented in the U. S. National Herbarium by specimens from Texas, Arizona, 

 and Mexico. 



Panicum grossarium Linn. Amccn. Acad. 5: 392. 1759. {Panicum adspersum 

 Trin. Gram. Panic. 116.1826; Icon. 2: 1. 169, 1S29.) This species is very distinct 

 from Panicum fuscum Swartz, and is at once recognized by its larger, lanceolate 

 leaves, 15-20 cm. long, 1.5-2 cm. wide, ciliate sheath margins, scabrous, not papil- 

 late rachis, and larger spikelets, which are 4 nun. long, prominently pointed, 

 the outer glumes sparingly tuberculate-hispid, not reticulate-veined. It is well 

 represented by the following specimens from Florida: St. Augustine, 176 T. H. 

 Kearney, jr., July 24, 1895; 6705 A. H. Curtiss, August 3, 1900; Sanibel Island, 

 292 J. H. Simpson, March, 1891; Key West, 5431 Curtiss, June 22, 1895; Sand 

 Key, Cape Sable, 3606 Curtiss, July 1880; no locality, A. AV. Chapman. A small 

 form of this species was also collected on l>allast at Philadelphia, Pennsylvania, 

 byF. Lamson-Scribner, Seiitember, 1881. 



This is apparently a distinct species and is so considered by Grisebach, Fl. Brit. "\V. 

 Ind. 546, although some of the Florida specimens referred to here are much 

 larger than the plant he described. 



Panicum carthaginense Swartz, Prodr. Yeg. Ind. Occ. 22. 1788, is apparently rep- 

 resented by a specimen collected on ballast at Mobile, Alabama, by Dr. C. Mohr, 

 September 16, 1891. This species is of doubtful value and should perhaps be 

 considered as a synonym of Panicum fuscum Swartz or as a variety of that species. 



Panicum capillare Linn. Sp. PI. 86. 1753. 



University grounds, Tucson, No. 1520; near Pearce, No. 1938; Cochise, No. 1918, a 

 small form related to Panicum barbijyulriiKttum Nash. 



Panicum cognatum Schultes, Mant. 2: 235. 1824. (P. dirergens Muhl. 1817, not 



H. B. K. 1815; P. autumnale Bosc. 1825.) 

 Benson, No. 1833; Dragoon Mountains, No. 1862. 

 Panicum colonum Linn. Syst. Nat. ed. 10, 870. 1759. 

 Papayo Reservation, No. 1655; University grounds, Tucson, Nos. 1518 and 1534, 



forms approaching Panicum crus-gaUi Linn. 



Panicum crus-gaUi Linn. Sp. PI. 56. 1753. 



Benson, No. 1993; Papayo Reservation, No. 1671; Fairbank, No. 1970; Tucson, No. 

 1616. All these numbers represent the awnless form, which has been called var. 

 muticum by various authors, although all are somewhat diffei'ent from the Euro- 

 pean specimens and those of the eastern United States so referred. 



Panicum hallii Yasey & Scribn. Bui. Torr. Bot. Clul), 11: 61. 1884. 

 Mescal, No. 1813. 



