1915] 



GREENMAN MONOGRAPH OF SENECIO 



577 



II. Biennial or perennial herbs (rarely 

 annual). 



1. Stems herbaceous. 



* Heads usually radiate; flowers 

 yellow, except in 8. Grecnei 

 and 8, crocatus. 

 f Stem leafy to the inflor- 

 escence ; leaves laciniately 

 pinnatifid to triternately 

 divided. 



0. Native species § 2. 



00. Introduced species ...§ 3. 

 ff Stem not uniformly leafy to 

 the inflorescence; leaves pin- 

 nate or the lower simple 

 and undivided. 

 0. Leaves pinnate or pin- 

 natisect, rarely undi- 

 vided § 4. 



00. Lower leaves rotund- 

 ovate, simple and un- 

 divided § 5. 



fff Stem not uniformly leafy 

 to the inllorescence; leaves 

 simple and entire to lyrate- 

 pinnatifid; plants either 

 quite glabrous from the 

 start or more or less per- 

 manently tomentose; pu- 

 bescence never of long 

 jointed hairs. 



0. Plants glabrous or 



early g 1 a b r a t e ; 

 leaves upwardly re- 

 duced on the stem . . § 6 - 

 00. Plants at first tomen- 



tose, later glabrate; 

 leaves more uniform 

 throughout and 

 mostly pinnately di- 

 vided § 7. 



000. Plants permanently 



tomentose or more 

 or less glabrate ; 

 stem-leaves upward- 

 ly reduced § 8. 



fttfStem leafy to the inflo- 

 rescence (except in §9); 

 pubescence usually of long 

 jointed hairs. 



0. Stem-leaves not am- 



plexicaul. 

 5. Leaves not digi- 



tately divided . . § 9. 

 55. Leaves digitately 



divided §10. 



00. Stem - leaves amplexi- 



caul. 



Eremophili 

 Jacobaeae 



Sanguisorboidei 



Bolanderiani 



Aurei 



Lobati 



Tomentosi 



Columbian* 

 Digitati 



5. Involucre ecaly- 



culate §11- 



55. Involucre calycu- 



late § 12. Amplectentesi 



Cineraroidt % 



