198 FOUNDERS OF OCEANOGRAPHY 



streams can be traced far out to sea ; the Porcupine Bank 

 and the Rockall Bank are parts of the continent of Europe 

 which have sunk, there are submerged forests with peat 

 and tree trunks and remains of land animals in many places, 

 and on the west coast of Africa the bed of the Congo has 

 been traced as a submarine canon as far out to sea as the 

 1,000-fathom line. But these are only local oscillations of 

 the continental margins. In addition, lost continents have 

 been supposed to exist in mid-Atlantic and the Indian Ocean, 

 and if every atoll indicates the position of a sunken peak, a 

 vast area of the Pacific must, according to some views, have 

 been occupied by mountain ranges. 



It is not only geologists and oceanographers who have 

 imagined the existence of former continents where we now 

 have deep sea, but zoologists and botanists also have postu- 

 lated extensive former land connections in order to account 

 for the present distribution of land animals and plants — and 

 some of these connections did undoubtedly exist, while 

 others are still matters of controversy. Britain was certainly 

 connected with the continent of Europe both to the south 

 and the north in Tertiary times, and Europe was once 

 connected with North America by way of Iceland and 

 Greenland. The Antarctic continent was probably much 

 larger in former times, and may possibly have joined New 

 Zealand and Australia and connected the southern extremi- 

 ties of America and even Africa. The ancient granitoid rocks 

 of the Seychelles probably indicate a former land connection 

 (part of " Gondwanaland ") from South Africa through 

 Madagascar to Ceylon and India, dividing the Indian Ocean 

 into two seas ; and the present floor of the Indian Ocean is 

 supposed to have been formed by sinking in upper Cretaceous 

 times. There may also have been a land extension in 

 Cretaceous times between Brazil and the west coast of Africa. 

 But there was probably always an open Pacific Ocean and 

 some kind of a North Atlantic, although the eminent 

 Austrian geologist Suess supposed that the North Atlantic 



