APRIL, 1904. PLANTS YUCATAN^: MILLSPAUGH & CHASE. 145 



Achillea Millefolium L. Sp. PL, 899. 



An erect herb, simple or branched above, with striate, pubescent 

 stem and alternate, sessile (or basal petioled) finely dissected -pinnati- 

 fid, softly pubescent leaves, lanceo- 

 late in outline. Inflorescence of ter- 

 minal, compound, crowded, convex 

 or flat-topped corymbs; branchlets 

 and pedicels striate, pubescent. Heads 

 5 mm. high, 6 mm. broad; ray flow- 

 ers 5, disk flowers 12-15. Involucre 

 ovoid, bracts thin membranaceous with 

 a thick midrib, oblong, subacute, 

 softly pubescent, long ciliate, resin 

 dotted, outer shorter, narrow. Rays 

 white, ligule orbicular, 3 dentate, 2 

 mm. long, spreading; disk corollas 

 yellow, 5 lobed, resin dotted. Recep- 

 tacle convex; scales oblong, fim- 

 briate-ciliate. Achenes stramineous 

 or white when mature, 1.6 x 2-2.2 mm., oblong-cuneate, apex truncate; 

 in section unequally biconvex, the ventrum usually obtusely angled ; 

 glabrous. 



Hab. Campo about Merida, not in flower, April> 1887, Millspaugh 

 47. Doubtless introduced with imported hay. 



Called "ALCANFOR" in Yucatec. 



ARTEMISIA L. Sp. PL, 845. 



Heads heterogamous, discoid, the outer i or 2 series, pistillate, 

 fertile, with small slender tubular corolla; inner flowers perfect, fertile 

 or sometimes sterile, tubular. Involucre ovoid or oblong, its bracts 

 imbricated in few series, appressed. Receptacle flat, convex or hemi- 

 spheric, naked. Achene laterally compressed, 2 ribbed or striate, the 

 apex usually bearing an epigynous disk. Bitter aromatic herbs or 



shrubs with small heads disposed 

 in polycephalous panicles. 



Artemisia mexicana Willd. ex 



Spreng. Syst., 3:490- 

 Perennial by offshoots, stem 

 striate, whitened with cottony to- 

 mentum or nearly glabrate, branch- 

 ing above; leaves alternate, ses- 

 sile or attenuate into a petiole, 

 narrow, lanceolate to linear, 3-5 

 cleft, radical cuneate, incisely pin- 

 natifid or trifid, densely clothed with 

 white cottony tomentum on the 

 lower surface, sparingly so on the 



upper. Inflorescence an elongated leafy panicle of ascending, bracte- 

 ate racemes. Heads 4-4.5 mm - n 'gh> 2 mm. broad, 10-20 flowered, 



