E. L. EKMiN, WEST INDIAN VERNONIJE. 67 



Vernonia rigida Sw. 



Tabula nostra III, fig. 1 (inflorescentia). 



Conyza rigida Swartz, 1788, p. 113. 



Vernonia rigida Swartz, 1806, p. 1322; De Candolle, 1836, p. 49; 

 Grisebach, 1861, p. 354, syn. omnibus exclusis. 



Vernonia fruticosa Gleason, 1906 b, p. 182 haud V. fruticosa (L.)Sw. 



Pappi setae interiores persistentes, numero 25 30, firmae, 

 crassiusculae, paullulo complanatae, brunneae, quam exteriores 

 distinctae lanceolato-spathulatae circ. 6-plo longiores. Flores 

 desunt. Achaenia tenuiter sericeo-pubescentia. 



Hab. in Jamaica boreali: in montibus calcareis, petrosis 

 rarius, Swartz (H, K, M, Prodr, S, orig. spec, U, herb. 

 Thunb.). 



The species has, as far as I know, only been collected 

 by Swartz. 



The problem of the affinities of this species has caused 

 botanists much trouble. Swartz himself, in describing it, 

 supposed it to be closely allied to V. fruticosa (L.) Sw., 

 which, however, was not correct. Grisebach, in his Flora, 

 referred to it not only V. fruticosa, but also the species of the 

 subsection Sagrceana3, together with V. emarginata Wikstr. ! 

 Gleason at first followed Grisebach, identifying in his Re- 

 vision V. rigida and V. fruticosa, and placing them among the 

 Sagrazanai. Recently he has found that V. rigida is another 

 species than V. fruticosa, and that it is not to be placed to 

 his SagrcEanw. However, he does not mention anything about 

 the affinities of the species, authentic specimens of which he 

 has not seen. 



Having abundant material at hand of the species in ques- 

 tion, it was an easy matter for me to ascertain that V . rigida 

 Sw. is quite different both from V. fruticosa, V. emarginata, 

 and Vernonice Sagrosanai. Its relationships, however, still 

 remained questionable, until in an examination of the unnamed 

 Compositae of the Stockholm Herbarium I lighted upon a Ver- 

 nonia from the West Indies collected by Swartz, and presented 

 by him to the Swedish botanist Montin, which Vernonia 

 had some characters of V. rigida and some of V. acuminata 

 Less. Through this fortunate incident I was enabled to state 

 that the nearest ally of V. rigida is V. acuminata Less. A 



