5 
The location and extent of the formations admirably show 
any lateral variation that may exist, as individual zones may be 
followed for long distances and five of the formations are ex- 
posed on both the north and south shores of the island, and thus 
exhibit deposits in their relations to the ancient coasts. 
The English Head formation shows little variation through- 
out the entire extent of its exposures. To the east it appears to 
contain a little more shale than to the west, but the difference 
is not conspicuous. 
The Vaurial formation in its southern exposures is largely 
composed of nodular limestone and grey shales, the shales not 
prominent and for the most part occurring as shale partings. 
On the north shore in the exposures extending from Oil river 
to the eastern limit of the formation it consists of interbedded 
blue and grey shales and flaggy limestones. At the top are 
zones of sandy shale. Corals are extremely common in portions 
of the southern exposures, but are rare in the northern exposures. 
A Beatricia (Aulacera Plummer.) zone is present in this form- 
ation on both sides of the island, but is barely represented in the 
exposures on Vaurial river. In the northern exposures this zone 
contains an abundance of the bryozoan, Batostoma billingsi, 
and the brachiopod, Rhynchotrema janea, is quite common. 
Both of these forms are very rare in this zone on the south. 
The Ellis Bay formation in its southern exposures begins 
with about 7 feet of dark-blue calcareous shale, which is immedi- 
ately followed by nodular fine-grained limestones. In the 
middle portion it contains a great deal of calcareous shale, a 
coral reef limestone, and other limestones of variable character- 
istics. It ends with nodular, fine-grained limestones like those 
near the base. On the north shore the rocks are decidedly 
different; the shales are not calcareous, but sandy, and there is 
about 180 feet of sandstone. The correlation on opposite shores 
of the island is made certain by the presence of a Beatricia zone 
on both sides, with the fossils characteristic of this zone on the 
south shore also present on the north. Sandstones and sandy 
shales are absent in the Vaurial River section, not more than 
30 miles to the southwest of the sandstone occurrences, and the 
sequence resembles that of the south shore. These differences 
are certainly due to deposition at different distances from th 
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