562 MR. G. BENTHAM ON COMPOSITA. 
American character, but common also in the Old World. Two also 
of the three or four species of Erigeron and one of the four or five 
Helichrysa are colonists only, the former of American, the latter 
of South-African origin. There remain sixty-three genera, com- 
prising about 180 species, which may be regarded as indigenous. 
Amongst these there are three genera (all Canarian), and about 
ninety species (or half the total number) belonging to thirty 
genera, apparently endemic, the character of which we will con- 
sider under the separate groups of islands. Of the sixty appa- 
rently indigenous genera not confined to the Atlantic islands, five 
(Laggera, Pluchea, Pegolettia, Sclerocarpus, and Blainvillea, all 
from the southern Cape-Verd group) are African, but not at all, 
or scarcely, Mediterranean; the remaining fifty-five are all either 
essentially of a Mediterranean character, or are widely spread, or 
even cosmopolitan genera well represented in the Mediterranean 
region. 
The Azores, the most northern of these groups, appear to have 
only twenty Composite, natives or colonists, the natives all Me- 
diterranean species, except five belonging to the genera Bellis, 
Tolpis, Sonchus, and Microrhynchus, all chiefly or exclusively Me- 
diterranean. Seubert enumerates seven endemic Composite ; but 
the Solidago azorica, Seub., which is said to form so striking a 
feature on the sea-coast, is evidently the same as S. mexicana, 
Liun., a maritime plant from the southern coasts of North Ame- 
rica, which must be regarded asa colonist in the Azores, although 
we may have no evidenee as to the time or mode of its introduc- 
tion. It is also believed that Seubert’s Tolpis nobilis is only 
a luxuriant large-flowered form of T. macrorhiza, DC., from 
Madeira. 
The Canary Islands with Madeira exhibit rather more of the 
insular character. Out of about 150 species of Composite, one 
half are endemic. Only three genera have that character; but to 
these might be added the endemic sections Argyranthemum of 
Chrysanthemum, Pericallis and Bethencourtia of Senecio, Clavena 
of Carduus, Carlowitzia of Carlina, and Atractylis Preauxii, which 
are all endemic groups of higher than specific value. There are 
tracts of country within the Mediterranean region, perhaps not 
of much greater extent, where an equal number of endemic races 
might be found, but never any thing near so large a proportion, 
the total number of Composite being everywhere much greater 
than those of the Canary Islands. 
