454 SUBANTARCTIC ISLANDS OF NEW ZEALAND. [Systematic Botany. 



But although a phanerogamic flora does not exist at the present time, geologists 

 have long considered it probable that in the south polar regions, as has long been 

 known to be the case in the Arctic Zone, a much milder climate once existed, with 

 its natural accompaniment of a luxuriant vegetation. Proof of this has now been 

 obtained on opposite sides of the Antarctic Continent — near the head of Koss Sea, in 

 the veins of carbonaceous matter discovered by Ferrar during the " Discovery " Ex- 

 pedition, and in the beds of coal observed by Shackleton in his recent adventurous 

 journey towards the South Pole ; and in the more important, because more complete, 

 discovery of two fossil floras made by Dr. Anderson on the islands flanking Graham 

 Land, during the Swedish Antarctic Expedition led by Nordenskiold in the years 

 1902-3. According to the well-known palaeo -botanist Nathorst, in whose hands the 

 collections made by Anderson have been placed, and who has contributed a short 

 preliminary account to the Paris Academy of Sciences, they prove the existence, in 

 the first place, of a Jurassic flora remarkably rich in species, including Equisetineae, 

 ferns, and conifers, its general character resembling that of the Jurassic flora of 

 Europe, and particularly that of the Upper Gondwana in India ; secondly, a Tertiary 

 flora, including specimens of a Sequoia or of some allied genus, an Araucaria allied to 

 A. braziliensis, leaves of Fagus, and various small-leaved Dicotyledons. The im- 

 portance of this discovery can hardly be overestimated, and a full exploration of the 

 localities will probably throw a flood of light on the composition of the former vege- 

 tation of the Antarctic Continent, and give great aid in working out the origin of 

 southern floras generally. 



A vast sea, formed by the confluence of the southern portions of the Pacific, 

 Atlantic, and Indian Oceans, everywhere surrounds the Antarctic Continent, com- 

 pletely cutting it off from the land-masses to the north. The average depth of the 

 Southern Ocean at a distance of about 500 miles from the continent las teen esti- 

 mated by Sir John Murray at not less than 1,700 fathoms, or nearly tMo miles. So 

 far as is known, this great depth is wonderfully regular and constant ; and, as Sir 

 John Murray remarks, " There is no trustworthy evidence of ridges, barriers, or 

 banks extending far northwards from Antarctica." The distances which separate 

 the Antarctic Continent from the land-areas to the north are also very great, as may 

 be gathered from the following table : — 



Miles. 



Cape Horn to Graham Land . . . . , . . . 550 



Macquarie Island to Adelie Land . . . . . 970 



New Zealand (Stewart Island) to Victoria Land . . 1,625 



Tasmania to Adelie Land . . , . . . . . 1,600 



Kerguelen Island to Enderby Land . . . . . . 1,225 



Cape of Good Hope to Enderby Land . . . . 2,150 



At the present time, and with our present knowledge, the depth and width of this 

 ocean are the chief difficulties in the way of accepting any theory of previous land 

 connection with the Antarctic Continent. 



Proceeding northwards from Antarctica, we next arrive at a ring of scattered 

 islands, all of small size, and placed at vast distances apart, mere dots on an immense 

 expanse of ocean, which encircle the globe between lat. 45° and 60° S. The islands 

 to the south of New Zealand, whose vegetation it is the business of this memoir to 



