THE AMERICAN FAUNA AND ITS ORIGIN. 
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Islands, the Cape Verde Islands, Madeira, St. Helena, and 
Fernando de Noronha, all of which have seas of more than 
1,000 fathoms depth separating them from continental land, 
and so have been considered oceanic islands. 
The permanence of Ocean Basins, which the Atlantis 
hypothesis opposes, is an important subject, and has engaged 
the attention of very eminent men. Amongst those in favour 
of that permanence may be mentioned Huxley, Wallace, Sir 
Archibald Geikie, Asa Gray, and Professor Oliver, who based 
their conclusions on the higher specific gravity of the earth's 
crust below the oceans, the general absence of sedimentary 
rocks in oceanic islands, the absence of deep sea deposits in 
continents, and the agreement of plant and animal life and 
the present arrangement of land areas. In his Presidential 
Address to the Geological Society in 1890, Dr. Blanford 
examined these grounds in detail, and then expressed the 
opinion, “ that whilst the general permanence of ocean basins 
and continental areas cannot be said to be established on any- 
thing like firm proof, the general evidence in favour of this 
view is very strong.” 
Amongst those who have favoured the opposite conclusion 
are Lyell, Darwin, Edward Forbes, Andrew Murray, Heer, 
Unger, Leidy, Hutton, Guppy, Newmayer, Von Ihering, Suess, 
Laparent, and Dr. Scharff. Although I have the utmost 
respect for the opinions of these authors, I must confess that 
I fail to find anything in geology or zoological distribution 
requiring such a complete change of the geography of the 
world as would be effected by continental land occupying areas 
where now are the deepest parts of the oceans. While 
recognizing the cogency of the before-mentioned arguments 
for the permanence of ocean basins, I will venture to add one 
more which I hope may contribute to give the “ firm proof ” 
that Dr. Blanford desired. 
The former elevation of the floors of the abysmal depths of 
the oceans above the surface of the sea has been accepted, I 
think, in a large measure from the assumption of the globe 
having but a thin solid crust, which is vertically mobile and 
flexible. Thus by its flexibility wrinklings on a stupendous 
scale would follow an accommodation of the exterior to the 
shrinkage of a cooling interior, and so oceanic depressions and 
continental elevations would be found in different areas at 
different times. Such an amount of flexibility, indeed, has 
been assumed, that Croll ascribed the great northern depression 
following the Glacial Period to the weight of the glacial ice. 
