Aristida amerieana Linn., is an extrenielj- variable species and extends from 

 Kansas to Arizona, Lower California, Mexico, and the West Indies. It is 

 a ctespitose, much branched perennial 'i to 6 dm high, with rather short 

 involute leaves and many-flo\vered i)anicles 5 to 15 cm. long. Spikelets 8 to 

 10 mm. long, fasciculate; empty glumes usually purplish, uneiiual, the first 

 one-half to two-thirds as long as the second, which about equals the flower- 

 ing glume. Awns subequal, 1 to 1.5 em. long. 

 Specimens Examined. — A'rtH.sa.s; sandy soil, Comanche Coimty, 888 A. S. Hitch- 

 cock, 1896. re.ra.s-.- " Western Texas," 741 C.Wright, October, 1849, also 

 30 V. Havard, September, 1883, Limpia Canyon, 163 G. C. Nealley, Sep- 

 tember, 1892; Abilene, H. L. Bentley, 1899. Neir Mexico: Mangos Valley, 

 J. G. Smith, September 22, 1896; Organ Mountains, G. R. Vasey, 1881. 

 Arizona: Fort Huachuca, Dr. T. E. Wilcox. 1894; Santa Catalina Moun- 

 tains, 13 J. W. Tourney, April 3, 1894. Mexico : Guaymas, 66 E. Palmer, 

 1887; Mexican Boundary, near White Water, 2264 E. A. Mearns, September 

 11, 1893; Saltillo, State of Coahuila, 388 E. Palmer, September, 1898; also 

 1352, E. Palmer, 1880; Durango, State of Durango, 535 E. Palmer, August, 

 1896; Chihuahua, 390 C. G. Pringle, August, 1885. Loicer California: 504 

 E. Palmer, 1887. Dutch West Indies: St. Croix, 64 A. E. Ricksecker, 

 November 11, 1895. Forto Rico: 'o^uanica, 3438, 3766 P. Sintenis, 1886. 

 Aristida amerieana bromoides (H. B. K.) Scribn & Merrill, U. S. Dept. Agr., 

 Div. Agros., Cir. 32:5. 1901. [Aristida bromoides B.. B. K. Nov. Gen. et 

 Sp. PI. 1:122. 1815; Aristida dispersa bromoides Trin. &. Rupr. Agrost. 

 3:130. 1842; C'/icefaHa 5romoides R. & S" Syst. 2 : 396. 1817). 

 A low tufted form 1 to 3 dm. high, with slender, simple or branched culms, 

 short involute leaves and densely-flowered purplish or pale panicles 2 to 5 

 cm. long. Spikelets as in Arnstida amerieana. 

 In dry soil, Texas to California (Mexico). 



Specimens EXAMINED : Texas: Guadaloupe Mountains, 67 V. Havard, 1881. New 

 Mexico : between Santa Fe and Canoncito, 3754 A. A. & E. G. Heller, June 

 33, 1897; Santa Fe, 1325 A. L. Mulford, September 16, 1895, Socorro, G. R. 

 Vasey, 1881. Arizona: Santa Catalina Mountains, 14 J. W. Toumey, April 

 20, 1894; near Bisbee, 1027 E. A. Mearns, October 5, 1892, also 861 Mearns, 

 September 14, 1892; Quitovaquito, 2759 E. A. Mearns, January 30, 1894; Con- 

 gress, C. R. Orcutt, April, 1896; Ehrenberg, W. M. Canby, September, 1874; 

 Valley of the Colorado, 542 E. Palmer, 1876. Nevada .- Rioville, 5034 M. E. 

 Jones, April 12, 1894. California: near Saratoga Springs, 259 Coville & 

 Funston, February 2, 1891, The Needles, 3788 M. E. Jones. May 3, 1884; 

 Santa Catalina Islands, T. S. Brandegee, May 16, 1890. Lower Calif urnia : 

 near Indian Wells, 20:53 C. R. Orcutt, February 5, 1890: San Julio, 12 T. S. 

 Brandegee, 1889; Guadalupe Island, 669, 675 E. Palmer, 1889; Cedros Island, 

 665 Palmer, 1889; Santa Rosalia, 270 E. Palmer, 1890; no locality, 503 E. 

 Palmer, 1887. Mexico : Sonora, Guadalupe Canyon, 2033 E. C. Merton, Aug- 

 ust 27, 1893; Guaymas, 270 E. Palmer, 1890; Valley of Mexico, Federp.l 

 District, 6227 C. G. Pringle, November 4, 1895. 

 This variety is distinguished from Aristida amerieana by its smaller size, smaller 

 panicles, usually less branched culms and more ctespitose habit of growth. 

 We have assumed this form to be Aristida bromoides H. B. K., but may be 

 wrong in so interpreting it. The form here considered is doubtless Aristida 

 wa?ia Steud. Norn. ed. 2. 1:131. 1840. 



B. Culms simple, awns 2 to 8 cm. in length. 



Aristida longiseta Steud. Syn. PI. Gram. 420. 1855. [Aristida fascicidata 

 nuttallii Thurb. in Beal, Grasses N. A. 2:208. 1896.) 



