INTRODUCTION. 19 



of more than 1000 fathoms was dry land within 

 comparatively recent geological epochs. Thus the 

 Azores are classed by Darwin and Wallace among 

 the oceanic islands that is to say, among such 

 as have received their fauna and flora by flotsam 

 and jetsam. But Professor Neumayr believes, on 

 geological grounds, that the Old and New Worlds 

 were connected by a land-bridge during Tertiary 

 times right across the Atlantic, and that the 

 Canary Islands, Madeira, and Azores (p. 547) 

 are the last remnants of this continent. This 

 meets with the entire approbation of Dr. von 

 Ihering, who has recently re-investigated the sub- 

 ject from a faunistic point of view (p. 135). Take 

 another instance of one of Wallace's most typical 

 oceanic islands, the Galapagos Group. Their fauna 

 and flora have recently been most thoroughly 

 re-explored by an American expedition, the result 

 of which, according to Dr Baur, goes to show 

 that these islands must have formed part of the 

 mainland of South America at no distant date. The 

 fauna and flora are therefore to be regarded as having 

 reached them in the normal mode, viz., by migration 

 on land. According to Mr. Beddard (p. 138), it is 

 difficult to see how earthworms could be transported 

 across the sea. Floating tree-trunks have been ob- 

 served far out at sea, but unless the water remained 

 absolutely calm during the long period necessary for 

 the drifting by currents so that no splashing occurred, 

 the worms would probably be killed. Yet earthworms 



