504 MR. G. BENTHAM ON COMPOSITE. 
yet their geographical connexions and presumable origin may be 
assimilated to the few genera of that Table whose Asiatic character 
approaches or even exceeds the American. The single species of 
Centratherum, Flaveria, Soliva, and Trichocline, identical with, or 
closely representative of, corresponding American species of essen- 
tially American genera, suggest doubts whether they are ancient 
(or even modern ?) colonists from America or really remains of 
an ancient common flora. The Chiliotrichium and Olearia, the 
Plagiocheilus and Leptinella, the Abrotanella and the Microseris, 
and even the Centaurea form part of that general Antarctic flora 
which in so many orders shows a striking connexion between 
Australia (especially South-east Australia and Tasmania), New 
Zealand, and the southern extremity of South America, the Micro- 
seris and Centaurea showing in Australia the extreme end of an area 
extending from the northern extratropieal Old World over North 
Ameriea down the western backbone of the New World to the 
extreme south, and thence to Australasia. Australia, therefore, 
in regard to America, would appear once to have had in the south 
an antarctic or mountain connexion or communication sufficient 
for the interchange of races, to have received in the north in 
ancient times, as part of the Indo-Australian region, a few tropical 
or subtropical American races, and in ancient, as in recent, times 
to have readily admitted and favoured the spread of colonists 
from America as well as from South Africa, and more recently 
from Europe. 
Table 8. Endemic Species of cosmopolitan or very widely 
spread Genera. 
I include under this head those genera or groups of genera 
which have endemic representatives both in the New and the Old 
World, and both in the northern and in the southern hemisphere. 
The numbers given are necessarily very vaguely estimated for the 
northern and tropical regions, and must be taken rather as rela- , 
tive than as absolute; those for South Africa and Australia, 
founded on already worked-up floras, will be found more accurate. 
Such cosmopolitan or widely spread species as Gnaphalium luteo- 
album, Erigeron linifolium, Pluchea indica, Cotula coronopifolia, 
&c. are omitted, as having nearly the area of the genus, at least 
in their own primary division of the globe. Senecio has no such 
cosmopolitan species. 
