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cific Ocean by way of a now submarine plateau (p. 433) “from Guinea 
and North Australia, through the Fiji and Tonga Islands to Samoa, 
spreading South to New Zealand and North to the Ellice, Gilbert, Mar- 
shal, Caroline and Pelew Islands;” another plateau “extends from Chili 
in a northwest direction to the Society Islands and Cook’s Islands, in- 
cluding Juan Fernandez, Easter Island, the Paumotus and the Marquesas 
Islands.” Thus these two plateaus closely approached each other, if they 
were not actually connected. 
Shortly after Hutton’s first publication, Gill (1875) presented another 
somewhat similar view, but this was given in a very vague form. Con- 
sidering the distribution of fishes, he divided the land masses in two large 
sections, an Eogceci , comprising Africa, South America and Australia, and 
a Ccznogceci , comprising the rest of the present continental masses. He 
does not introduce the Antarctic continent at all, and does not give any 
details of the connection, simply intending this as a zoogeographical di- 
vision. But the fact that he calls these two sections “areas of derivation 
or gain from more or less distant geological epochs,” and that he refers 
to them again later ( Science , 8 June, 1900), calling them “hemispheres,” 
makes it apparent that he understood his Eogaea as a large continental 
mass. 
Thus we have to distinguish, practically, three different theories, aside 
from Wallace’s: (1) The Ruetimeyer-Hutton theory of the connection 
through an Antarctic continent (1867, 1873); (2) Gill’s Eogaea theory 
( 1 875) ; (3) Hutton’s theory of 1884, constructing a connection across 
the mid-Pacific. In all these, the fundamental idea first expressed by 
Hooker, that there must once have been a connection by land, serves as 
a basis. 
Gill’s theory has never been taken up by anybody else, while the two 
other theories have been taken into consideration by subsequent writers. 
Among them we should mention in the first line H. O. Forbes (1893). 
He practically accepts the first and oldest theory of Ruetimeyer and 
Hutton, in assuming the former existence of a larger Antarctic continent ; 
but on the other hand, he goes far beyond Ruetimeyer’s and Hutton’s 
ideas, in constructing this continent on a very large scale: his “Antarc- 
tica,” in its coast line, follows nearly what is now the 2000 fathom line, 
and extends in broad stretches over Australia and New Zealand to the 
Fiji Islands, to the Mascarene Islands and South Africa, and to South 
