THE ANTAKCTIC ESSAY 425 



But besides its historical interest in relation to the Species 

 Question, the Essay contained what was up to its time the most 

 scientific treatment of a large area from the point of view of the 

 Plant- Geographer. He found that the Antarctic, like the Arctic 

 Flora, is very uniform round the globe. The same species in 

 many cases occur on every island, though thousands of miles 

 of ocean may intervene. Many of these species reappear on 

 the mountains of Southern Chili, Australia, Tasmania, and 

 New Zealand. The Southern Temperate Floras, on the other 

 hand, of South America, South Africa, Australia, and New 

 Zealand differ more among themselves than do the Floras of 

 Europe, Northern Asia, and North America. To explain these 

 facts he suggested the probable former existence, during a 

 warmer period than the present, of a centre of creation of new 

 species in the Southern Ocean, in the form of either a continent 

 or an archipelago, from which the Antarctic Flora radiated. 

 This hypothesis has since been held open to doubt. But the 

 fact that it was suggested shows the broad view which he was 

 prepared to take of the problem before him. His method was 

 essentially that which is now styled ' Ecological.' Many hold 

 this to be a new phase of botanical enquiry, introduced by 

 Professor Warming in 1895. No one will deny the value of 

 the increased precision which he then brought into such 

 studies. But in point of fact it was Ecology on the grand scale 

 that Sir Joseph Hooker practised in the Antarctic in 1840, 

 Moreover it was pursued, not in regions of old civilisation, but 

 in lands where Nature held her sway untouched by the hand 

 of man. 



This Essay on the Flora of the Antarctic was the prototype 

 of the great series. Sir Joseph examined the Arctic Flora from 

 similar points of view. He explained the circumpolar uni- 

 formity which it shows, and the prevalence of Scandinavian 

 types, together with the peculiarly limited nature of the Flora 

 of the southward peninsula of Greenland. He extended his 

 enquiries to oceanic islands. He pointed out that the condi- 

 tions which dictated circumpolar distribution are: absent from 

 them ; but that other conditions exist in them which account 

 for the strange features which their vegetation shows. He 

 vol. n 2 e 



