FEB. 1903. PLANTS YUCATAN^: MILLSPAUGH & CHASE. 



47 



Aristida nigrescens Presl. in Rel. Haenk. 1:223. 



Panicle short-exserted, 15-20 

 cm. long, branches alternate, 

 spreading or ascending; axis and 

 rachis smooth. Spikelets 18-20 

 mm. long, on slender pedicels. 

 First and second glumes plum- 

 color, lanceolate, acuminate, 

 i-nerved, first 5. 8 mm., hispid on 

 the nerve, second 8 mm. gla- 

 brous; floral glume 6.5 mm. ex- 

 cluding awns, stramineous mot- 

 tled with plum-color, mid-nerve 

 hispid, lateral nerves hispid 

 above; awn trifid, scabrous, mid- 

 dle awn divergent, 14 mm., lat- 

 eral awns suberect, 12 mm.; 

 palea 8 mm., hyaline. Grain 

 light brown, linear - lanceolate, 

 obtuse, .35x5.3 mm.; in section 

 convexo-concave. 

 Hab. Merida, Aug. 1865, Schott 601, Oct. 1865, 6$6a. 



Aristida bromoides H. B. K. 



Nov. Gen. 1 1122. 



Aristida Americana L. f. ? 



Aristida dispersa Trin. & 

 Rupr. 



Panicle exserted or nearly 

 so, 10-15 cm ' l n g> branches al- 

 ternate, short, ascending; axis 

 and rachis scabrous. Spikelets 

 20-22 mm. long on slender ped- 

 icels. First and second glumes 

 purplish, lanceolate, acuminate, 

 i -nerved, the first 6.5 mm. long, 

 hispid on the nerve, the second 

 9 mm., glabrous; floral glume, 8 

 mm. excluding awns, pale 

 stramineous, hispidulous on the 

 midnerve above; awn trifid, sca- 

 brous, middle awn divergent, 17 

 mm. long, lateral awns sub- 

 erect, 14 mm.; palea i mm. or 

 less, hyaline. Grain light brown, 

 linear-lanceolate, obtuse, .6x7 mm.; in section elliptic. 



Hab. San Anselmo, 10 inches high, Gaumer 1206, Izamal 

 Chichankanab 224.8. 



