12*. ASCLEPIADACEAE. 16J. 



4. Corona lobes filiform, or linear and divided into 2 — 3 filiform 



segments. Stipules a line connecting bases of petioles. 



3 TACAZZEA. 

 Corona lobes broadly obcordate. Stipules toothed or frill- 

 like. 4 CHLOROCODON. 



5. Pollen masses 2 in each anther half, 4 on each carrier, very 



small. 5 SECAMONE. 



Pollen masses 1 in each anther half, 2 on each carrier. 6. 



6. Pollen masses contained in the lower part of the anthers, 



pendulous from the arms of the pollen carriers. 



(Asclepiadeae.) 7. 



Pollen masses in the upper part of the anthers, attached to 



the pollen carriers in an erect, ascending or horizontal 



position. 2I. 



7. Corona lobes free or nearly so, except in Cynanchum. Stems 



erect or procumbent, never twining. 8. 



Corona lobes usually united high up. Stems twining or 



rambling. 17. 



8. Corona lobes united in a tube. 16 CYNANCHUM. 

 Corona lobes free or nearly so. 9. 



9. Corona lobes distinctly concave or laterally compressed, 



sometimes with a horn-like process within the cavity. 10. 



Corona lobes flat or rather flat or dorsally compressed or 



very fleshy but not concave, sometimes with keels or 



processes on the base. I2. 



10. Corona lobes exceeding corolla, strongly keeled all down 



the back with a rhomboid winglike expansion on the 



back at the base. Apex incurved. 10 KREBSIA. 



Corona lobes not as in Krebsia. 11. 



11. Sepals without basal glands. Corona lobes with large ap- 



pendages on the inside margins, ascending staminal 

 column as narrow wings. 6 WOODIA. 



Sepals with basal glands, solitary or paired. Corona lobes 

 more or less laterally flattened with or without a horn 

 from the central cavity. 13 ASCLEPIAS. 



12. Corona lobes very thick and fleshy, or if moderately fleshy 



then without an appendage or with 1 keel on the inner 

 face. 7 XYSMALOBIUM. 



Corona lobes thin or flattened dorsally, rarely somewhat 

 fleshy and then with 1 — 2 appendages or 2 keels on inner 

 face. 13. 



13. Flowers large and showy, white with a purple corona. Corona 



lobes with 2 erect basal lobules, but no keels. Corolla 



lobes sub-erect. 12 FANNINIA. 



Not as for Fanninia. I4. 



14. Staminal column (stigmatic head) subglobose from being 



constricted at apex and base. 8 PERIGLOSSUM. 



