APRIL, 1904. PLANTS YUCATAN^: MILLSPAUGH & CHASE. 1 1 1 



pubescent toward the summit, fimbriate-ciliate. Corollas white, rays 

 bidentate; disk flowers narrowly campanulate, 5 toothed. Receptacle 

 conic; scales obcordate, tomentose and erose at the summit. Achene 

 black, 1.2x2 mm., obovate; in section triangular in outline, the dor- 

 sum convex, the ventral angle rounded and facets concave; densely 

 clothed with brownish white, thickened hairs; pappus of 2 slender 

 erect cartilaginous awns, .2 mm. long, hardly visible- among the 

 hairs. 



Hab. San Anselmo, Gaumer 2115; border of lagoon south of 

 Progreso, March 5, 1899, Millsfaugh PL Utowance i6(5j. 



SANVITALIA Lam. Journ. Hist. Nat, 2:176, t. 33. 



Heads heterogamous, radiate; rays pistillate, fertile, ligulate; per- 

 sistent on the achene; disk flowers perfect, fertile, tubular. Involucre 

 depressed hemispheric, of herbaceous bracts imbricated in 2-3 

 series. Receptacle convex to conic, chaffy; scales enfolding the disk 

 flowers, persistent on the receptacle. Achenes heteromorphous, ray 

 achenes triangular, dorsally compressed, 3 awned; disk achenes later- 

 ally compressed, winged or wingless, 2 awned or awnless. Annual 

 herbs with rather showy heads of yellow rays and dark purple disks. 



Sanvitalia procumbens Lam. Journ. Hist. Nat., 2:176, t. 33. 



A diffuse, procumbent annual, with subangled stem and branches, 

 and opposite, petioled, lanceolate-ovate, strigose leaves. Inflorescence 

 of solitary heads terminating the slender, hirsute branches. Heads 

 7-8 mm. high, 12-15 mm - broad, subtended By 2-3 foliaceous, hirsute 

 bracts; rays 8, disk flowers numerous. Involucral bracts orbicular, 

 appressed, with foliaceous spreading ciliate tips, pubescent, the inner 

 little exceeding the outer. Rays yellow, turning white in fruit, ovate, 

 5-6 mm. long, minutely biden- 

 tate; disk corollas dark purple, 

 5 lobed. Receptacle convex to 

 conic; scales lanceolate, condu- 

 plicate, exceeding and partly en- 

 folding the disk flowers. Achene 

 of ray flowers cineraceous black 

 when mature, 1.2x3 mm., oblong 

 cuneate; in section triangular; 

 tuberculate, hirsute at the base, 

 awns 3, divergent, 2 mm. long; 

 achenes of disk flowers dull 

 brown, .85x2 mm., obovoid, in 

 section plano-convex to rhom- 

 boidal biconvex; with one or a 

 pair of loosely cellular, ciliate- 

 fimbriate wings, 5-7 mm. wide, 

 or wingless; the winged with i or 2 awns, 1-2 mm. long or awnless, 

 faintly tuberculate; the wingless achenes awnless and covered with 

 tubercles each tipped by a short stiff hair or its stub. 



