390 C. SKOTTSBERG 



sition of the local subantarctic floras, rich in herbaceous plants belonging to many 

 different families and orders, land communication must have persisted to middle 

 or even late Tertiary times. That the connection goes far back is shown by the 

 occurrence of a Gondwana flora on both sides of the Drake passage (Graham 

 land, Falkland Islands), and the Cretaceous rocks of South Georgia prove, as 

 HOLTEDAIIL says, the existence of a land mass of considerable size where there 

 is now sea. Joyce (<5-f) remarks that "there is good evidence that the Scotia Arc 

 with its extension into West Antarctica has persisted as a structural feature since 

 Lower Palaeozoic times". 



The Scotia passage offers one of the migration routes over land that we are 

 in need of, but another passage, the iMacquarie route between East Antarctica 

 and Australia-New Zealand is required to make the trans-antarctic route complete. 

 There are intermediate islands, Macquarie, Auckland and Campbell Islands, with 

 a subantarctic flora suggesting former connections, and there are tracts with shal- 

 lower water between Tasmania and the continent, but for want of geological evi- 

 dence this bridge is hypothetical, and many authors prefer to speak of submerged 

 intermediate islands sufficiently close to facilitate the spread of organisms able 

 to cross moderate water barriers. As AxELROD says [14.. 183): 



Archijielagoes of only slightly greater extent than those now present could account 

 for the continuity of the Antarcto-Tertiary Flora in all these regions during the early 

 and middle Cenozoic. 



Florin, referring to the present and former distribution of conifers, expressed 

 himself in similar terms. 



Antarctica has ])layed an important role in the development and distribution of 

 the southern group of conifers. The data related to its distributions considered in this 

 paper seem most readily explained by assuming land connections, or at least much 

 closer proximity between Antarctica and the adjacent southern ends of South America, 

 Australia, New Zealand and South Africa (95.92), 



and after the discovery of a Tertiary species q{ Acuwpylc in Patagonia and a sec- 

 ond fossil form in the TLocene of Seymour Island, he wrote [33S. 136): 



Fur cine ehemalige Verkniipfung der australischen Region mit der Antarktis spricht 

 auch die Verhreitung der Gattung Acmopyle. Dass also die Antarktis in diesem Falle 

 als cine alte Vermittlerin zwischen der australischen Region und Siidamerika gedient 

 hat, muss meines Erachtens angenommen werden. 



However, one of the supposed links, Macquarie Island, does not, it seems, 

 possess any plants, perhaps not even mosses or lichens, dating back to the height 

 of the Glacial lY^riod, fcjr this island was, at least during maximum glaciation, 

 entirely ice-covered and must, Tavlor says, have received its present plant world, 

 very poor it is true, in postglacial time from the north and across a considerable 

 stretch of open sea [263). In Antarctica proper the situation is, with regard to 

 lichens and mosses, different. Dahe [^2. 231), basing his opinion on the discovery 

 of numerous endemic lichens and of a few mosses not very far from the south 

 pole, concludes that part of the flora survived the glaciations. Here, where high 



