237 
times been gradually subsiding. Further, the remarkable submarine forests 
in the Bay of Fundy show that within a time not sufficient to produce the 
decay of pine-wood, this depression has taken place to the extent of at least 
40 feet, and probably to 60 feet or more. We have thus direct geological 
evidence of a former higher condition of the land, which may, when at its 
maximum, have greatly exceeded that above indicated, since we cannot trace 
the submarine forests as far below the sea-level as they actually extend. The 
effect of such an elevation of the land would be not only a general shallowing 
of the water in the Bay of Fundy and the Acadian Bay, and an elevation of 
its temperature both by this and by the greater amount of neighbouring 
land, but, as Professor Verrill well states, it would also raise the banks off the 
Nova Scotia coast, and extending south from Newfoundland, so as to throw 
the Arctic current further from the shore and warm the water along the 
coasts of Nova Scotia and Northern New England. In these circumstances 
the marine animals of Southern New England might readily extend them- 
selves all around the coasts of Nova Scotia and Cape Breton, and 
occupy the Acadian Bay. This modern subsidence of the land would 
produce a relapse toward the glacial age, the Arctic currents would be 
allowed to cleave more closely to the coast, and the inhabitants of the 
Acadian Bay would gradually become isolated, while the northern animals 
of Labrador would work their way southward. Various modern indications 
point to the same conclusions. Verrill has described little colonies of 
southern species still surviving on the coast of Maine. There are also dead 
shells of these species in mud-banks, in places where they are now extinct. 
He also states that the remains in shell-heaps left by the Indians indicate 
that even within the period of their occupancy some of these species existed 
in places where they are not now found. Willis has catalogued some of 
these species from the deep bays and inlets on the Atlantic coast of Nova 
Scotia, and has shown that some of them still exist on the Sable Island 
banks. Whiteaves finds in the Bradelle and Orphan bank littoral species 
remote from the present shores, and indicating a time when these banks were 
islands, which have been submerged by subsidence, aided, no doubt, by the 
action of the waves. It would thus appear that the colonization of the' 
Acadian Bay with southern forms belongs to the modern period, but that it 
has already passed its culmination, and the recent subsidence of the coast 
has, no doubt, limited the range of these animals, and is probably still 
favouring the gradual inroads of the Arctic fauna from the north, which, 
should this subsidence go on, will creep slowly back to reoccupy the ground 
which it once held in the post-pliocene time. 
“ Such peculiarities of distribution serve to show the effects of even com- 
paratively small changes of level upon climate and upon the distribution of 
life, and to confirm the same lesson of caution in our interpretation of local 
diversities of fossils, which geologists have been lately learning from the 
distribution of cold and warm currents in the Atlantic. Another lesson 
which they teach is the wonderful fixity of species. Continents rise and 
sink, climates change, islands are devoured by the sea or restored again from 
its depths ; marine animals are locally exterminated and are enabled in the 
course of long ages to regain their lost abodes ; yet they remain ever the 
same, and even in their varietal forms perfectly resemble those remote 
ancestors which are separated from them by a vast lapse of ages and by 
many physical revolutions. This truth, which I have already deduced from 
the post-pliocene fauna of the St. Lawrence Valley, is equally taught by the 
mollusks of the Acadian Bay, and by their Arctic relatives returning after 
long absence to claim their old homes.” 
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VOL. IX. 
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