1915] 



GREENMAN — MONOGRAPH OF SENECIO 617 



flowers 12 to 15, rays oblong, 10 to 12 mm. long; disk-flowers 

 numerous j achenes about 3 mm. long, ribbed, slightly pubes- 

 cent on the ribs. 



Distribution: eastern Mexico. 

 Specimens examined: 



Hildago: Zimapan, Coulter 423 (Kew Herb.), type. 

 Tamaulipas: near Miquihuana, alt. 2140 to 2740 m., 10 

 June, 1898, Nelson 4492 (Gray Herb, and U. S. Nat. Herb.). 



Sect. 5. Bolanderiani Greenm. 



§5. Bolanderiani Greenm. Monogr. Senecio, I. Teil, 22, 

 23. 1901, and in Engl. Bot. Jahrb. 32 : 18, 19. 1902. 



Slender, herbaceous perennials; stems erect or nearly so, 

 1 to 5 dm. high, from a slender more or less horizontal root- 

 stock; leaves undivided and orbicular-ovate to pinnatifid; 

 heads of medium size, about 1 cm. high, radiate ; achenes glab- 

 rous. Sp. 30-32. 



A. Stems 1.5 to 5 dm. high, leafy to the inflorescence. 



a. Leaves usually pubescent beneath; bracts of the 



involucre G to 9 mm. long, more or less hairy. . 80. S. Bolanderi 



b. Leaves glabrous on both surfaces; bracts of the 



involucre 5 to 6.5 mm. long, glabrous 31. 8. Harfordii 



B. Stems 1 to 2 dm. high, leafy only at the base 82. 8. Flettii 



30. S. Bolanderi Gray, Proc. Am. Acad. 7 : 362. 1868 ; Bot. 

 Calif. 1 : 411. 1876, in part ; Syn. Fl. N. Am. I 2 : 392. 1884, and 

 ed. 2, 1886, in part ; Howell, Fl. N. W. Am. 1 : 379. 1900, in part ; 

 Greenm. Monogr. Senecio, I. Teil, 23. 1901, and in Engl. Bot. 

 Jahrb. 32 : 19. 1902. 



A slender herbaceous perennial; stems ascending or erect, 

 from a creeping rootstock, 1.5 to 5 dm. high, striate, often 

 somewhat purplish; radical and lower stem-leaves undivided 

 and crenately lobed-dentate to pinnately divided into oblong, 

 obovate to subrotund, crenate to sharply dentate divisions, 

 glabrous above, usually pubescent beneath, including the 

 petiole .5 to 1.5 dm. long, 1 to 3 cm. broad; the upper stem- 

 leaves sessile; inflorescence terminating the stem in a few- 

 headed subcorymbose cyme ; heads 10 to 12 mm. high, radiate ; 

 involucre campanulate, calyculate, usually tawny pubescent; 

 bracts of the involucre about 13, linear-lanceolate, 6 to 9 mm. 



