1902. The British Association in Belfast, 281 



was derived from the adjoining continents of Europe and Africa by 

 winds and hurricanes. The weight of the arguments brought forward 

 by Wallace silenced all critics for a time, and the influence of 

 his views is traceable in most of the more recent writings on the 

 subject. But since some leading geologists have expressed themselves 

 against the theory of the permanence of the great ocean basins, the 

 older views of a possible land-connection between Europe and the 

 Atlantic Islands, and also between Europe and America, are again 

 discussed. The author has, therefore, collected together a number of 

 facts in the distribution of animals which had not hitherto been utilised, 

 in order to make a renewed attempt from a zoological point of view to 

 solve the Atlantis problem. 



The results of these investigations tend to show that Madeira and the 

 Azores are the remains of an ancient Tertiary area of land which was 

 joined to Europe, and that it probably became disconnected in Miocene 

 times. Since then this land once more became united with our continent, 

 and may not have been finally severed until the Pleistocene period. 

 As regards the question of a land -bridge across the Atlantic, many 

 reasons can be given in favour of such a theory. It must, however, have 

 occupied a position farther south than the land just alluded to. Uniting 

 North Africa with Brazil and Guiana in early Tertiary timec, it probably 

 subsided during the Miocene period, leaving only a few isolated peaks as 

 islands in the midst of the vast ocean which has since replaced it 



Prof Poui^TON, in opening the discussion on this paper, reminded the 

 Section that the doctrine of the permanence of ocean basins originated 

 not with Wallace but with Darwin, whose conclusion seemed unshaken 

 by the facts brought forward by Dr. ScharfF and those whom he had 

 quoted. Our knowledge of distribution in most groups was still too 

 imperfect to warrant us in creating continents. 



Prof. Dendy followed on the same side, and thought that the American 

 element in the fauna of the Canaries might be explained by chance 

 carriage of organisms by the Gulf Stream. 



Mr. Carpenter believed that the admitted imperfection of our know- 

 ledge could not invalidate the positive distributional facts cited by Dr. 

 ScharfF, and considered that the number of correspondences now known 

 could not be explained by any theory of chance introduction by winds and 

 currents, pointing out that some of the most characteristic animals 

 common to Europe and the Atlantic Islands, such as the slugs of 

 the genus Testacella, live deep underground. 



Dr. Stanley Gardiner dwelt on the fact that the flora and fauna of 

 coral islands must be carried to them by currents. 



Prof. Wei^dox thought that there was much weight in Dr. Scharff' s 

 contentions, since the living MoUuscan fauna of the Atlantic Islands 

 shows a close likeness to the Continental Miocene fauna. 



Dr. Scharff, in reply, instanced the case of the British operculate 



mollusc Cyclostoma—a.n animal specially adapted for spreading its range 



by means of water-carriage. Yet, although dead shells are frequently 



being washed on the Irish coast, the animal has never been able to 



establish itself here. 



D 



