580 
Sinnott and Bailey . — The Origin and 
earlier and much more uniform flora which flourished over the earth during 
the middle or latter part of the Tertiary, and before the great flood of 
herbaceous vegetation, developed chiefly in the north temperate lands, had 
spread far over the globe. 
This conclusion is strengthened by the many similarities which these 
widely separated island floras bear to one another. 
The arborescent or shrubby Compositae of Hawaii, Tahiti, the Gala- 
pagos, and Juan Fernandez are all related, and those of St. Helena are also 
characteristically American, rather than African, in type. Woody species 
of Plant ago occur only in Hawaii, Juan Fernandez, and St. Helena. 
On Juan Fernandez flourish three species of W ahlenbergia, a South 
African genus with several species on St. Helena ; Sophora tetraptera , 
growing elsewhere only on Easter Island, New Zealand, and Chile ; Gunner a, 
from South America, South Africa, Australasia, and Hawaii ; Coprosma , 
found elsewhere only in New Zealand and Hawaii, and one or two other 
genera and species with very scattered distribution. The endemic 
arborescent genus of Labiatae, Cuminia , is much like the shrubby Bysiro- 
pogon of western South America and the Canary Islands. Woody Borra- 
ginaceae occur in the Canaries, St. Helena, and Juan Fernandez ; the genus 
in the latter group, Selkirkia i resembling in floral structure Myosotidium of 
the Chatham Islands. 
Melhania , of St. Helena, is close to the Mascarene Trochetia ; Psiadia , 
an otherwise exclusively Mascarene genus, has a species in St. Helena, and 
there are similar species of Acalypha and Carex in both places. 
Several plants from the Canaries, such as Prenanthes pendula , Carpy - 
lanthus salsoloides , Euphorbia arbuscula , and others, approach very closely 
species from Socotra. There is also a distinct American element in the 
flora of the Canaries, and a much stronger affinity still with South Africa 
and the Mascarene region. 
The flora of Socotra contains species of Graderia and Camptoloma , 
genera otherwise confined to South Africa ; and of Campy lan thus, elsewhere 
found only in the Cape Verde and Canary Islands and in Baluchistan. 
A well-marked American affinity is shown by the presence of Thamnosma , 
Dirachma , and Coelocarpus. The genera Elaeocarpus and P or ana flourish 
in Madagascar, Australia, and Socotra, but not in Africa. 
In the Mascarene region, aside from the forms already mentioned, 
occur the genera Labourdonnaisia (Natal and Cuba), O cotea (Canaries and 
South Africa), and Mathurina (from Rodriguez), which is close to the 
Central American Erblichia. 
Almost all the larger oceanic islands, therefore, have floral affinities 
with several other oceanic islands or with distant continental areas, and this 
fact strengthens the belief that these highly peculiar insular floras are 
isolated vestiges of a very ancient vegetation which was much more uniformly 
