768 PATAGONIAN /EXPEDITIONS I BOTANY. 



A^. Heads dioecious or polygamo-dicecious. 



b. Receptacle of female flowers with large pales. 20. Hcterothalamus, p. 800. 



b2. Receptacle without pales. Dioecious. 2.l.'Sacckaris,p.8cn, 



Tribe IV. Inulece. (Genera 22-32), p. 810. 

 A. Female flowers filiform. 

 b. Receptacle naked. 



c. Styles of the hermaphrodite flowers with filiform, pointed branches, having collecting 

 hairs. Heads solitary or crowded, but not glomerulate. Achenes small, pappus of many 

 slender setae. Shrubs or half-shrubs, with leafy stems and broad, involucrate bracts. 

 d. Involucrate bracts membranous or leathery. Hermaphrodite flowers numerous. 



22. Pluchea, p. 810. 

 d2. Involucrate bracts dry, coriaceous, mostly recurved. Hermaphrodite flowers 



rather few (i-io). 23. Tessaria, p. 810. 



2. Styles of the hermaphrodite flowers mostly truncate, and only with a terminal ring of 

 hairs ; stigmas as marginal lines. Style in sterile flowers obtuse, clavate or capitate. 

 Heads heterogamous or abortively dioecious. 



d. Achenes rostrate. All the flowers with a pappus. 26. Chevreulia, p. 81 1. 

 d2. Achenes not rostrate. 



e. Hermaphrodite flowers all unfruitful, with undivided or lobed style. Dioecious 

 herbs, with alternate leaves, and many-flowered heads having numerous in- 

 volucral scales. 27. Antennaria, p. 812. 



e2. Hermaphrodite flowers equally or mostly fertile. 



f. Pappus-setae plumose, on a basal ring. Style branches not truncate. An- 

 nual herbs, branching below. 28. Facelis, p. 813. 

 /2. Pappus setae not plumose. 



g. Heads small, few-flowered (3-6 female, and 1-2 hermaphrodite). 



29. Achyrocline, p. 813. 

 g2. Heads many-flowered, rather small, cylindrical. 



30. Lucilia, p. 814. 



g$. Heads many-flowered, hemispherical, or ovoid or campanulate. Fe- 

 male flowers 2 several-seriate. Head only exceptionally solitary, 

 mostly glomerulate. 31. Gnaphalmin,p. 814. 



bz. Receptacle paleaceous before all or at least the female flowers. Mostly woolly herbs, 



with entire or toothed leaves, and small, not ribbed, achenes. 

 c. Chaff enclosing the female flowers, with corolla terminal on the achenes. Pappus none, 



at least in the female flowers. 24. Psilocarphus, p. 8 1 1 . 



C2. Female flowers only i-2-seriate, enclosed in chaff. Pappus a toothed or jagged 



crown. 25. Micropsis, p. 811. 



A2. Female flowers ligulate. Style-branches obtuse. Receptacle without chaff. Disk-flowers 

 sterile. Pappus none or a small ring. Stigmas marginal, apically coalescing. 



32. Adenocaulon, p. 819. 



Tribe V. Helianthoidece. (Genera 33-41), p. 820. 

 A. Receptacle chaffy throughout. 



b. Corolla of female flowers none or very small. Heads monoecious. 



