SOUTH ATLANTIC LAND BRIDGE 875 



the' Cretaceous of Patagonia and New Zealand, the Eocene 

 of Egypt, England and India, and the Miocene of Egypt and 

 Malta. The faunistic relationship between Patagonia and New 

 Zealand will be explained later on, yet it has by no means been 

 produced by a sub-universal distribution. The only fossil oc- 

 currence of Podocnemis we know of from Africa is that from 

 Egypt, and even that, with Malta and England, is rather sug- 

 gestive of a radiation from a Mediterranean centre. The 

 dispersal from an originally Patagonian birthplace may have 

 taken place westward to New Zealand and northward along 

 the ancient land connection, which I described as extending 

 by way of Central America to southern Europe. It is impor- 

 tant to bear in mind this very peculiar case of faunistic rela- 

 tionship between South America and Madagascar, exclusive 

 of the African continent, because similar instances are met 

 with among many groups of animals and plants. I have 

 already alluded to one, and it was first suggested by Dr. 

 H. 0. Forbes, I think, that this range was due to a former 

 direct land connection between Patagonia and Madagascar. 

 I drew attention in a former chapter (p. 173) to the 

 members of the family Amphishaenidae as furnishing, on 

 account of their subterranean habits, important evidences 

 of former changes of land and water. I may men- 

 tion again that they are limbless, wormlike liazrds, and 

 that many of them live underground in ants' nests. They 

 are not liable, therefore, to accidental dispersal. Their 

 distribution is most interesting. They inhabit mostly Africa 

 and South America. A few occur in the West Indies and 

 the Mediterranean region. Some have even spread into the 

 southern States of North America, and we possess a few 

 remains from Oligocene deposits. Otherwise we know nothing 

 of their past history. We might suppose that some early mem- 

 ber of this family had spread across the mid-Atlantic land 

 bridge to the Mediterranean region and thence colonised 

 Africa with Amphisbaenidae. But in this instance such a 

 land bridge cannot help us, because the genus Amphisbaena 

 occurs in Africa and South America, while the Mediterranean 

 region is inhabited by the genus Blanus. The latter, no doubt, 

 may owe its origin to a migration across this mid-Atlantic 

 land bridge, still we can scarcely imagine that, coming from 



