649 ON FITCHIA, A NEW GENUS OF COMPOSITÆ. 
than half the native flowering plants being different from those 
of the American continent. Twenty-one are Composite, (di- 
vided into 13 genera), all but one peculiar; 3 of these genera 
are arborescent or frutescent, and include 8 species. 
Elizabeth Island is situated in the Pacific Ocean, and 
although we know little of its Botanical productions, there 
is every probability that they are, in a great measure, identical 
with those of Pitcairn’s, and other islands of the Low Archi- 
pelago, and the Society groups; all which are considered to 
rank under one Botanical region, including all the South 
Sea Floras. What I-would particularly notice here is, that in — 
none of these are any arborescent Cichoracee seen, or if —— 
Cichoracee at all, certainly none allied to Fitchia. This 
occurrence of a plant which appears characteristic of an — — 
American island, at the western extremity of a very widely — 
extended Botanical region, (wholly unlike the American), is 
a very singular fact, and we cannot help combining it with the 
circumstance, that, except Ducie's and Easter Islands, Eliza- 
beth Island lies nearer Juan Fernandez, (where arborescent —— 
Cichoracee chiefly abound), than any of the Pacific group. — 3 
Thus there is a sort of union of two widely different and fno 
separated Floras, at the approximating point of their geogra- — — 
phical positions, and not caused by specific identity, which — 
migration would explain satisfactorily to many, but depen- 
dent on botanical characters, indicating an affinity equally 
decided, but of a far more puzzling nature. d 
I may conclude with a remark on the South Sea Flora 1n 
general. The similarity between the vegetable productions of 
all the Pacific groups is such as to have induced Botanists p 
consider them but subdivisions of one extended botanical — 
region. The similarity is, however, more apparent than real, and d 
mainly owing to the prevalence of some conspicuous littoral A 
species, with other plants transported by man to these isolated 
spots, as they were successively inhabited. There has been 
in short, a migration of man and plants from the westward, 
all over the Pacific Archipelago; but Iam inclined to suspect 
that these introduced species are superadded to a Flora that 
