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



95 



on long, bracteate peduncles, terminal and axillary; peduncles and 

 pedicels slender, somewhat flexuous, puberulent. Heads about 25 

 flowered, 5-5.5 mm. high, as broad or nearly so. Involucre cam- 

 panulate, bracts in 2-3 series, more or less spreading, the outer lanceo- 

 late, acute, cuspidate, puberulent; inner narrowly oblong, obtuse, 

 ciliolate-hyaline margined at the summit, exceeding the flowers. 

 Corolla light purple. Receptacle slightly convex. Achene black, 

 .35 x 1.3 mm. ; oblong, little narrowed at the base; in section 5 angled, 

 the dorsal facets usually convex; 5 nerved, the nerves hispidulous; 

 pappus bristles white, capillary, 2 mm. long. 



Hab. "Herb, 6 feet high, ataguadas near Izamal, not common, 

 October" Gaunter 1022. 



Eupatorium Guadalupense Spreng. Syst, 3:414. 



An erect, branching herb, with terete, striate, glabrate stem 



and branches, and opposite 

 and alternate, petioled, rhombic- 

 ovate, acute, crenate, nearly 

 glabrous leaves. Inflorescence a 

 loose, open, leafy, cymose pan- 

 icle; branches and pedicels slen- 

 der, puberulent. Heads about 15 

 flowered, 4-5 mm. high, as broad 

 or broader. Involucre campanu- 

 late, bracts in 2 or 3 series, 

 spreading; the outer lanceolate, 

 acute, puberulent; inner linear- 

 oblong, obtuse or minutely api- 

 culate, nerved, glabrous, much 

 exceeding the flowers. Corolla 

 violet. Receptacle flat. Achene 

 dark brown, .35-.4XI.5 mm., oblong, slightly rounded at apex and 

 larrowed at base; in section unequally 5 angled, the facets concave; 5 

 icrved, hirsute on the nerves above and sometimes sparsely so between 

 them: pappus bristles white, capillary, 1-2.5 mm - l n g> caducous. 



Hab. Cozumel, 1886 Gaumer (Oliver) {Eupatorium paniculatum 

 Schrad. Field Col. Mus. Bot. 1:51); "herb, 3 feet high, common," 

 Pocoboch, Gaumer 1317 ; Calotmul 2joj. 



Called XULTOXIU "Introduced weed" by the Mayas, who consider 

 the species exotic. 



WILLUGHB^EA* Neck. Elem., 1:82. 



Heads homogamous, discoid, flowers perfect, fertile. Involucre 

 oblong of few subequal bracts in 2 series. Receptacle naked, small, 

 plane. Achene 5 angled; pappus of many bristles in 1-2 series, con- 

 nected at base by an annulus. Herbaceous or woody vines, heads 4 

 flowered, in cymose or corymbose panicles. 



Achenes attenuate at the base, internerves glandular-puberu- ) cordifolia 



lent or glabrate \ 



Achene not attenuate, internerves resin dotted scandens. 



*The separation of this genus from Eupatorium is questionable. 



