1879. ] The Formation of Cape Cod. 563 
and Mississippi ; a Plicatula similar to P. filamentosa Conrad, and 
an Axinea, closely like A. staminea Conrad, both of the Alabama 
Eocene ; also probably Striarca centenaria Conrad, found in the 
Miocene of the Southern States. Other molluscan genera that 
were recognized are Corbula, Cardium, two species of Yoldia or 
Nuculana, several small Turritella-like species, and a small Natica. 
Echinoderms are represented by spines of a Cidaris, and ccelen- 
terates by a simple cylindrical Ga/axea-like coral. 
In this connection it is interesting to notice that fragments of 
fossiliferous rock,! apparently of Miocene age, are brought up 
from the sea-bottom on George’s Bank, Banquereau and the 
Grand Bank, by the coralline growths attached to them becoming 
entangled with fishermen’s lines. These, with the Eocene peb- 
bles of Cape Cod, show that the coast of New England, Nova 
Scotia and Newfoundland, one thousand miles in extent, is bor- 
dered by submerged Tertiary formations similar to those which 
occur above sea-level in the Southern States, as had been already 
suggested by Prof. C. H. Hitchcock? before these discoveries. It 
was a theory of Agassiz that the fishing banks, from which these 
Tertiary rocks are drawn up, represent the terminal deposits 
of drift accumulated at the front of the ice sheet. Both this and 
the theory of Prof. Hitchcock appear to be true, for besides the 
fossiliferous fragments many of granites and schists are also 
obtained by the fishermen. Furthermore the course of the 
extreme terminal moraine that crosses New Jersey, Long Island, 
Block Island, Martha’s Vineyard and Nantucket has its line of 
continuation in these remarkable submarine banks, which prob- 
ably consist, somewhat like Gay Head, of Tertiary strata covered 
with their own and foreign detritus brought by the ice-sheet. 
The moraine of Cape Cod, the Elizabeth islands, Southern 
Rhode Island and the north shore of Long Island, was formed 
after the ice had retreated from its farthest limit, but while it still 
terminated eastward beyond the present coast line. This halt in 
its departure was extended along the entire margin of these ice- 
fields to the west, for a distance of more than two thousand miles. 
Although in the interior of the United States the extreme limit 
of glacial action has not yet been found to be generally marked. 
by extraordinary deposits, a most notable series of terminal mo- 
_ __* Described by Prof. Verrill in American Yournal of Science and Arts, 3d series, 
Vol, xvr, p. 323. : 
* Appalachia, Vol. 1, p. 13, and Geology of New Hampshire, Vol. 11, p. 21. 
