1915] 



GREENMAN — MONOGRAPH OF SENECIO 575 



barium, the New York Botanical Garden Herbarium (includ- 

 ing the Torrey Herbarium), the Herbarium of the Field 

 Museum of Natural History, the Herbarium of the Phila- 

 delphia Academy of Natural Sciences, the Missouri Botanical 

 Garden Herbarium, and a number of private collections. To 

 the directors and curators of all these, as well as the owners 

 of the private herbaria, and correspondents who have facili- 

 tated my work, I wish to express personal thanks; but I 

 desire especially to extend most grateful acknowledgments to 

 Dr. Benjamin Lincoln Robinson, Asa Gray Professor of 

 Systematic Botany at Harvard University, and Geheimrath 

 Professor Dr. Adolph Engler, Director of the Royal Botanical 

 Gardens and Museum of Berlin, without whose cooperative 

 interest and extreme liberality in the use of valuable scientific 

 material under their charge, this work would have been im- 

 possible. I am also grateful to Mr. W. Botting Hemsley, of 

 the Kew Herbarium, through whose courtesy I secured type 

 material of certain rare Mexican species and a number of 

 excellent drawings, some of which are herein reproduced. 



I have cited exsiccatae rather freely, particularly such as 

 occur in American herbaria, but by no means all that have 

 been examined, and I have given even at the expense of much 

 repetition detailed citation of specimens in different herbaria, 

 hoping that this would be helpful in the interpretation of 

 species and to future students of the genus. The few plates 

 which it is possible to include are chosen to illustrate more 

 especially the different sections as here defined. 



SENECIO [TOURN.] LINN. 



Senecio [Tourn. Inst. 456. pi. 260. 1700] L. Sp. PI. 2 : 866 

 1753; Gen. PL, ed. 5, 373, n. 857. 1754; Hill, Hort. Kew 



25. 1768, and ed. 2, 1769 ; Juss. Gen. PL 181. 1789 ; Less. Syn 

 391. 1832; DC. Prodr. 6 : 340. 1837; Endl. Gen. 458, n. 2811 

 1838 ; Hook. Fl. Bor. Am. 1 : 331. 1840, in part ; Torr. & Gray 

 Fl. N. Am. 2 : 436. 1843 ; Benth. & Hook, f . Gen. PL 2 : 446. 1873 

 in part ; Pf eiffer, Norn. Bot. 2 2 : 1136. 1874; Hemsl. Biol. Cent.- 

 Am. Bot. 2 : 235. 1881, excl. Cacalia; Gray, Syn. Fl. N. Am 

 l 2 : 383. 1884, and ed. 2, 1888; Hoffmann in End. & Prantl. 



