JONES. — A REVISION OF THE GENUS ZEXMENIA. 151 



2-awned, the awns shorter than the body ; ray-achenes somewhat mar- 

 gined and the margins produced upward into 3 coarse teeth. — Mexico 

 Specimens examined, — Jalisco: Rio Blanco, Palmer, no. 757, coll. of 

 1886 (type, in herb. Gray). This species has been confused with Z. 

 aurea, but it is certainly quite distinct, being well marked by its thick- 

 ened lignescent base, the shape and pubescence of its leaves, long and 

 ciliated involucral scales, and large more or less margined ray-achenes. 



*+ ++ Suffruticose, fruticose, or arborescent. 

 = Rays purple. 



12. Z. zinnioides, Hemsl. Much-branched ; branches long, slender, 

 scabrous-pubescent, ferrugineous : leaves sessile or shortly petioled, rigid, 

 ovate-oblong, 5 to 9 cm. long, acute or obtuse, remotely serrulate or 

 subentire, sparsely strigillose-pubescent on both surfaces, shining above : 

 peduncles 1.5 to 2.5 cm. long, commonly solitary, pubescent; heads 

 about 1 cm. high ; involucre campanulate, usually 1 cm. broad ; bracts 

 about 16, appearing somewhat decussate, scabrous, the outer rather 

 broad, acute, the inner oblong or linear, glabrous, colored at the tip : 

 ligules 10 to 12, purple, broadly oblong; disk-corollas purple, funnel- 

 formed, papillose-hirsute on the limb : achenes margined ; awns about 

 as long as the body, rigid. — Biol. Cent.-Am. Bot. ii. 175 (1881). — 

 Northern Mexico. Specimens examined, — A portion of the type, 

 Seemann's no. 1464, collected on the Cerro de Pinal, and obligingly 

 sent from herb. Kew. 



= = Rays yellow. 

 a. Bracts unequal, in several series, the outer much the shortest. 

 1. Scales of the involucre recurved at the tip. 



13. Z. squarrosa, Greenman, n. sp. "Shrub; stems and branches 

 appressed sericeous-pubescent, often copiously dotted with lenticels : 

 leaves broadly ovate, 3 to 7 cm. long, 2 to 6 cm. wide, somewhat acu- 

 minate, dentate, cuneate or rounded at the base, tuberculate-hispid above, 

 paler and hirsute-pubescent on the prominently reticulated veins beneath, 

 3-nerved from the base; petioles 0.5 to 1.5 cm. long: peduncles terminal, 

 5 to 20 mm. long, cymosely arranged; heads 1 to 1.5 cm. high; invo- 

 lucre cylindrical or slightly turbinate, 5-6-seriate ; bracts ovate to oblong, 

 acute to rounded at the apex, conspicuously ciliate, the outermost shorter 

 ones pubescent on the dorsal surface and with subfoliaceous squarrose 

 tips : ray-flowers about 5, the ligules usually less than 1 cm. long, 

 lemon-yellow; disk-flowers numerous, considerably exceeding the in- 



