o34 Geographical Distribution of Animals 



where across from the Antilles and Guiana to North Afi-ica and South 

 Western Europe, existed an almost identical fauna of Corals and 

 JMolluscs, indicating either a coast-line or a series of islands interrupted 

 by shallow seas, just as one would expect if, and when, a Brazil- 

 Ethiopian mass of land were breaking up. Lastly from Central 

 America to the Mediterranean stretches one of the Tertiary tectonic 

 lines of tlie geologists. Here also the great question is how long this 

 continent lasted. Apparently the South Atlantic began to encroach 

 fi'om the south so that by the later Cretaceous epoch the land was 

 reduced to a comparatively narrow Brazil -West Africa, remnants of 

 which persisted certainly into the early Tertiary, until the South 

 Atlantic joined across the equator with the Atlantic portion of the 

 " Thetvs," leaving what remained of South America isolated from the 

 rest of the world. 



Antarctic connections. Patagonia and Argentina seem to have 

 joined Antarctica during the Cretaceous epoch, and this South Georgian 

 bridge had broken down again by mid-Tertiary times when South 

 America became consolidated. The Antarctic continent, presuming 

 that it existed, seems also to have been joined, by way of Tasmania, 

 with Australia, also during the Cretaceous epoch, and it is assumed 

 that the gi'eat Australia- Antarctic-Patagonian land was severed first 

 to the south of Tasmania and then at the South Georgian bridge. 

 No connection, and this is important, is indicated between Antarctica 

 and either Africa or Madagascar. 



So far we have followed what may be called the vicissitudes of 

 the great Permo-Carboniferous Gondwana land in its fullest imaginary 

 extent, an enormous equatorial and south temperate belt from South 

 America to Africa, South India and Australia, which seems to have 

 provided the foundation of the present Southern continents, two of 

 which temporarily joined Antarctica, of which however we know 

 nothing except that it exists now. 



Let us next consider the Arctic and periarctic lands. Unfortunately 

 very little is known about the region within the arctic circle. If it 

 was all land, or more likely great changing archipelagoes, faunistic 

 exchange between North America, Europe and Siberia would present 

 no difficulties, but there is one connection which engages much atten- 

 tion, namely a land where now lies the North temperate and Northern 

 part of the Atlantic ocean. How far south did it ever extend and 

 what is the latest date of a direct practicable communication, say 

 fi'om North Western Europe to Greenland? Connections, perhaps 

 often interrupted, e.g. between Greenland and Labrador, at another 

 time between Greenland and Scandinavia, seem to have existed at 

 least since the Permo-Carboniferous epoch. If they existed also in 

 late Cretaceous and in Tertiary times, they would of course easily 



