Page:A sketch of the physical structure of Australia.djvu/28

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of a white compact, rather argillaceous sandstone, which among others contains the following fossils :

Fossils from Point Puer.
Producta rugata.

Spirifer subradiatus.
—— crassicostatus, MSS., sp. n.
—— Stokesii.
—— Vespertilio

Pterinea macroptera.

Orthonota compressa.
Allorisma, n.s.
Pachydomus carinatus.
Pecten squamuliferus.

Eagle Hawk Neck, the connecting link of Tasman's and Forrester's Peninsulas, is one of the celebrities of Tasmania, on account of the peculiar jointed structure of its rocks, forming what is called "the tessellated pavement." The rock is a very hard, brittle, fine-grained and compact grey sandstone or gritstone, lying in a horizontal position. It occasionally contains pebbles of granite, porphyry, or quartz rock.

The rocks abound in fossils, especially at the south point of Pirates' Bay. Among others I collected fine specimens of the following:—

Fossils from Eagle Hawk Neck.
Fenestella internata.

Producta rugata.
Spirifer crebristriatus.
—— Darwinii.
—— avicula.

Spirifer subradiatus.

—— Vespertilio.
Platychisma Oculus?
Pachydomus carinatus.

On the opposite side of Norfolk Bay is a small peninsula about three miles across, in which is a large convict-station called The Mines. The mass of this piece of land consists of sandstone with some trap, but immediately at the back of the station is a small colliery. A bed of coal, of slight thickness and extent, is here worked. The following was the shaft-section as given me by the overseer:—

Yards.
"Ironstone" (a fine-grained trap rock) 20
Sandstone 20
Sandstone and shale 10
Coal