E. L. EKMAN, WEST INDIAN VERNONI^. 55 



umbrosis montis Llano, 6. 7. 86, Sintenis n. 4749 (D, KU, 

 P). — St. Jan: ad Küstenberg, alt. 210 m, 31. 12. 87, Eggers 

 n. 3256 (KU). — St. Croix: ex herb. Hornemann (B). 

 — Coll. ignot. (H). 



In collections from the tropics hybrids are only very 

 seldom found, apparently because the collectors have been 

 collecting by chance, without knowing the species. In our 

 case, however, the probability of getting the hybrid was a 

 greater one, both the parents, V. albicaidis and V. sericea, 

 being doubtless familiar to collectors like Eggers and Sin- 

 tenis. In fact, not less than four particular collections of 

 the hybrid have been made. 



The hybridous nature of our plant is clearly manifested 

 by the fact, that in all characters it is intermediate between 

 its supposed parents. It constitutes a particular type, having 

 characters of both parents, and only of them. Since V. al- 

 bicaidis and V. sericea have never been found to pass into 

 each other, it cannot be considered merely as an intergrad- 

 ing form. However, its pollen seems to be rather good. 

 The grains are somewhat cornered and dark-coloured, and 

 do not swell swiftly when boiled in milk acid and water. The 

 achenes are well evoluted. 



The best character of the hybrid is the length of its an- 

 thers. V. alhicaulis has large anthers, 2,5 mm in length, V . 

 sericea very small ones, only 0,8 mm long. Now the hybrid 

 has quite intermediate anthers, 1,6 mm in length. As to 

 the leaves it is rather variable, Eggers n. 3256 having leaves 

 of V . alhicaulis sensu strict, and Hornemann like those of 

 F. sericea. The inflorescence resembles that of F. sericea. 

 The involucres are larger than those of F. sericea, including 

 15 — 16 flowers (in V. sericea 11 — 13, in F. alhicaulis 20 — 21); 

 as to their form they are intermediate. The scales resemble 

 those of F. alhicaidis, yet the outer ones are cuspidate, as 

 in F. sericea, and the inner ones often somewhat purplish, 

 as in that species. The colour of the pappus is tawny. 



Yernouia boriiiquensis Urb. 



Tabula nostra II, fig. 7 (cyma). 



Vernonia arborescens Sw. var. Lessingiana Stahl, 1887, p. 103, p. p. 

 non Grtseb. 



