JOHNSTON. — A REVISION OP THE GENUS FLAVERIA. 291 



++ ++ Inflorescence densely corymbose, terminal on long stalks. 



12. F. VAGiNATA, Rob. & Greenm. Perennial with stout lignescent 

 root : stems several, ascending from a decumbent or even prostrate 

 somewhat branched base, terete, striate, purplish, with biliuiate short 

 grayish woolly pubescence, leafy above, naked below except for the per- 

 sistent and sheathing bases of the fallen leaves : internodes very short : 

 leaves linear-lanceolate, clasping at the base, very gradually attenuate, 

 often fascicled in the axils, l(-3)-nerved, rather pale green, finely ciliated 

 toward the base: heads small, closely aggregated into terminal solitary 

 or coryinbose-[)aniculate glomerules ; these simulating the normal involu- 

 crate heads of the order: glomerules .12 to .16 cm. in breadth, subtended 

 by a few short recurved foliaceous bracts, and containing 30 or more 

 heads : involucral scales 3 to 4 in each head, hyaline : ray-flower soli- 

 tary, conspicuous, .5 cm. long, with oblong slightly 2 to 3 toothed yellow 

 ligule : disc flowers 5 to 1 , yellow : style of 9 3-cleft : achenes black, 

 lucid, about 10-nerved, 9 2-25 mm. long, ^ acheue 1.75 mm. long. — ■ 

 Rob. & Greenm. Proc. Am. Acad, xxxii. 48 (1896). E. W. Nelson, 1933, 

 between Coixlahuaca and Tamazulupam, Oaxaca, alt. 2,000 to 2,500 m. 

 Nov. 1894. 



* * Heads 10- to 15-flo\vered. 



■t- Leaves linear to lanceolate, slightly connate. 



++ Ligulate flowers not present, inflorescence usually naked. 



13. F. LONGIFOLIA, Gray. Rather stout, 3 to 9 dm. high, pale: 

 leaves glabrous, broadest or not narrowed at the closely sessile base, 5 

 to 12.5 cm. long, entire or with rare spinulose deuticulations : heads in 

 regular very ample cymes, which are often destitute of leaves. — Gray, 

 PI. Fendl. 88. Gyinnosperma oppositifulia, DC. Prod. v. 312. — 

 Mexico : San Luis Potosi, Parry and Palmer, 498, 1878 (lib. Gr., hb. 

 Engel., hb. U. S.), also Pringle, 3767, July, 1891 (hb. Gr.) ; Parras, 

 Coahuila, Palmer, 685, 1880 (hb. Gr., hb. J. D. S., hb. U. S.) ; Saltillo, 

 Coahuila, Palmer, 304, Sept. 1898 (hb. Gr.) ; also Palmer, 681, 1880 

 (hb. Gr., hb. J. D. S., hb. U. S.) ; Tehuacan, Liebmann ace. Hemsl. 

 1. c. ; Berlandier, without locality (hb. Gr.) ; Cienega Grande, Gregg, 

 705, May, 1847 (hb. Engel.) ; Tamaulipas, Jaumam Valley, E. W. 

 Nelson, 4450, June, 1898 (hb. U. S., hb. Gr.). 



++ -w- Ligulate flowers present, inflorescence usually subtending a small whorl 



of leaves. 



14. F. floridana, nov. sp. Herbaceous, erect or ascending, branch- 

 ing dichotomous, branches often uuec^ual iu length, striate, glabrate; 



