JONES. — A REVISION OF THE GENUS ZEXMENIA. 153 



b. Bracts of the involucre subequal or the outer longest, in few series. 

 1. Outer bracts the longest, not foliaceous. 



16. Z. crocea, Gray. Much-branched shrub: leaves oblong-ovate, 

 subcordate, acuminate, short-petiolate, serrulate, reticulate-veiny, scab- 

 rous above, pilose beneath: peduncles often 12 cm. long, generally 

 thickened upward, hirsute, terminal and solitary or in a cyme of 3 ; 

 heads 1 to 2 cm. high; involucre 10 to 15 mm. broad, 2-seriate ; outer 

 bracts oblong-ovate to obovate or spatulate, acute or obtuse, strigose to 

 densely hirsute, much longer than the inner : ligules orange-yellow, 

 little or not at all exceeding the disk ; disk-corollas with long slender 

 tubes : acheues of the ray-flowers usually with 1 long awn and 2 short 

 teeth ; achenes of the disk-flowers about 5 mm. long, 1 to 2 mm. wide, 

 their awns unequal and shorter than the body. — PI. Wright, i. 114 

 (1852); Hemsl. Biol. Ceut.-Am. Bot. ii. 172; Seemann, Bot. Voy. 

 Herald, 305. Z. Stenantha, Hemsl. 1. c. 174 (1881). — Mexico. Spec- 

 imens examined, — Morelos : near Cuernavaca, Pringle, no. 6187 ; 

 near Yautepec, Pringle, no. 8701; Bourgeau, no. 1204. Oaxaca : 

 Huajuapam, Nelson, no. 1978. 



17. Z. Salvinii, Hemsl. Shrub, diffusely branched, with large leaves 

 and marked pubescence : leaves broadly-ovate, shortly petiolate, acute or 

 acuminate, serrate, scabrous above, pilose beneath : peduncles about 1 to 

 2 cm. long, pilose, bearing a few small bracteal leaves and a solitary 

 head; heads few, 10 to 15 mm. high; involucre about 1 cm. broad; 

 bracts apparently decussate, the outer 4 strigose, ovate-oblong or spatu- 

 late, brownish : ligules conspicuous, yellow, exceeding the disk and 

 involucre : achenes of the ray-flowers 3-augled, with 3 stout awl-shaped 

 awns, those of the disk-flowers 2-angled, cuneate, 4 mm. long, with 

 2 awns. — Biol. Ceut.-Am. Bot. ii. 173 (1881). — Central America. 

 Specimens examined, — Guatemala : Santa Rosa, Heyde $ Lux, nos. 

 3358 and 3797 of J. D. Smith's distrib. 



2. Outer bracts of the involucre not longer than the inner. 



18. Z. fruticosa. Rose. Diffusely branched shrub: leaves lanceo- 

 late or ovate, obtuse to subcordate at the base, acute or acuminate at the 

 apex, serrate, scabrous above, hispid-pubescent beneath, sessile or shortly 

 petioled : peduncles slender, 2 to 4 cm. long, somewhat exceeding the 

 upper leaves, chiefly terminal, solitary or in cymes of 3 ; heads about 

 1 cm. high ; involucre campanulate, 2-3-seriate, 5 to 7 mm. broad ; outer 

 bracts lax, ovate or lanceolate, hispid, ciliate, acute, somewhat shorter 

 than the inner: ray-flowers 5 to 10; ligules lemon-yellow, surpassing 



