BOTANY OF THE GUAYANA HIGHLANDS PART V 



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17. Lateral nerves on lower surface of leaf -blades 8-10 pairs; 

 leaf-blades obtuse to acutish, narrowly lanceolate to lanceo- 

 late-oblong; interior of corolla-tube completely glabrous; 

 involucre 7-8 mm high ; Colombia. S. revoluta. 



16. Petioles 0.9-2 cm long; leaf -blades 5.5-9 cm broad; Colombia. 



S. acuminata (form) 



15. Peduncle 2-14 cm long. 



17. Outer basal half of stipules puberulent; stigmas 3; Venezuela. 



S. yutajensis. 



18. Stipules glabrous throughout ; stigmas 2. 

 19. Corolla-tube glabrous within. 



20. Corolla in bud tapering to an elongated acuminate- 

 subulate apex; Colombia. S. neeoides. 

 20. Corolla in bud acute to obtuse or rounded at apex. 



21. Corolla-tube shorter than the lobes; involucre poorly 

 developed, 2.5 mm or less long (high) ; Colombia. 



S. stellata. 



21. Corolla-tube longer than or equaling the lobes; in- 

 volucre 2.5-16 mm or more long (high). 

 22. Heads 15-20-flowered ; corolla 11-20 mm long, the 

 tube 7-10 mm long ; lateral nerves of leaf -blades 



12- 14 on each side; Venezuela. S. glabriflora. 

 22. Heads 3-7 flowered ; corolla 22-37 mm long, the tube 



13- 21 mm long; lateral nerves of leaf -blades 5-9 on 

 each side. 



23. Leaf -blades rounded or obtuse at apex and base; 

 lateral nerves of leaf-blades 5-6, the tertiary vena- 

 tion poorly developed, not forming a close retic- 

 ulum; corolla 37 mm long, tube 21 mm long; 

 Cuba. S. cubensis. 



23. Leaf -blades acute to acuminate at base, obtuse to 

 acute at apex; lateral nerves of leaf -blades 8-11, 

 the tertiary venation more or less elevated and 

 reticulate; corolla 22-26 mm long, tube 13 mm 

 long; Trinidad, Venezuela. S. clnsiaefolia. 



19. Corolla-tube more or less pubescent within. 



24. Lateral nerves of leaf -blades 5-8 on each side or not 

 manifest. 



25. Leaf -blades abruptly acute or subaeuminate at apex; 

 inner cucullate appendage of corolla-lobe a blunt pro- 

 tuberance 0.5 mm long at 3-4 mm from apex; corolla- 

 tube infundibuliform, the expanded throat 9 mm 

 broad ; Venezuela. 8. hilliaefolia. 



25. Leaf -blades mainly rounded or obtuse (acute to acu- 

 minate in one variation of S. vahlii) at apex; inner 

 cucullate appendage of corolla-lobe conspicuous, trian- 

 gular to subulate, as much as 2.25 mm long at 5-12 

 mm from apex; corolla-tube salverform, the expanded 

 upper portion 4-5 mm broad; West Indies, Guianas, 

 Brazil. 



26. Orifice of corolla densely pilose; Brazil. S. brasiliensis. 

 26. Orifice of corolla naked, the pubescence confined 

 below the orifice; West Indies, Guianas, Brazil. 

 27. Leaf-blades mainly 2 1 / 4~3 1 /2 times as long as 

 broad, usually narrowed or tapering at base and 

 apex; calyx truncate or subtruncate, entire at 

 margin: Guianas and Brazil. S. polycephala. 



27. Leaf-blades mainly l 1 /2-2 1 / 4: times as long as 

 broad, usually rounded, obtuse, or subacute at 

 base and apex; calyx usually lobed or repand at 

 apex; West Indies. 



