[Vol. 2 



578 ANNALS OF THE MISSOURI BOTANICAL GARDEN 



** Heads discoid; flowers whitish or 



purplish, 

 f Heads 2 cm. or more high ; 



corollas deeply 5-lobed §13. Rugeliae 



■j-f Heads 1 cm. high; corollas 



shortly 5-toothed § 14. Mulgcdifolii 



2. Stems ligneous at the base. 



* Involucre barely calyculate ; 

 plants densely white-tomentose 

 throughout § 15. Incani 



** Involucre calyculate; plants 



glabrous or pubescent § 16. Stiff ruticosi 



3. Shrubs or tree-like plants §17. Fruticosi 



/3. Leaves palmately veined §18. Palmatinerves 



7. Leaves pinnately veined; lateral nerves 



parallel-arcuate, numerous and conspicuous.. § 19. Multinervii 



h. Stems abruptly terminated by a fore-shortening 

 of the main axis and bearing at the top two to 

 several, more or less pedunculate axillary com- 

 pound corymbose cymes; oil-tubes richly de- 

 veloped in the peripheral portion of the stem.. §20. Terminates 



B. Stems climbing § 21. Strcptothamni 



Subgenus II. Pseudogynoxis Greenm. Style-branches ter- 

 minated by triangular acute or acuminate dor sally hispidulous 

 appendages §22. Convoivuioidd 



Subgenus I. Eusenecio Hoffm. 



Subgenus I. Eusenecio Hoffm. in Engl. & Prantl, Nat. 

 Pflanzenf . IV. Abt. 5. 297. 1892 ; Greenm. Monogr. Senecio, I. 

 Teil, 21, 30. 1901, and in Engl. Bot. Jahrb. 32 : 17, 26. 1902. 



Annuals, biennials or perennials; stems erect, scandent or 

 climbing ; leaves pinnately or palmately veined ; heads radiate 

 or discoid; style-branches truncate or rounded-obtuse, not 

 infrequently bearing a penicillate tuft of hairs at the extreme 

 tip. Sect. 1-21. 



Sect. 1. Annui Hoffm. 



§ 1. Annui Hoffm. in Engl. & Prantl, Nat. Pflanzenf. IV. 

 Abt. 5, 297. 1892; Greenm. Monogr. Senecio, I. Teil, 21, 23. 



1901, and in Engl. Bot. Jahrb. 32 : 17, 19. 1902. Obaejacae DC. 

 Prodr. 6 : 341. 1837. 



Annual herbs; heads radiate or discoid; involucre nar- 

 rowly campanulate or subcylindric, usually calyculate; 

 achenes pubescent or glabrous. Sp. 1-7. 



