File:The Quarterly journal of the Geological Society of London (13365754894).jpg

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PROCEEDINGS OF THE GEOLOGICAL SOCIETY. .Maicll 13,
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Gulf of St. Lawrence.
quartzite prevail. Westward of the main
stream of the St. Mary's River, clay slate and
quartzite with masses of granite are the pre-
vailing rocks.
The surface of this metamorphic belt is
rugged and uneven, but not very elevated.
The inland side is however somewhat higher
than the parts nearer the coast, attaining in
some places an elevation of about 600 feet ;
it abounds in small lakes and streams, and its
coast line is much indented.
From the upper part of the west branch of
the St. Mary's River to the head of Cheda-
bucto Bay, the granitic group is bounded on
the north by a valley occupied by sandstones,
conglomerate, and shale, composed of the de-
bris of the hypogene and metamorphic rocks ;
and containing a few Calamites and other
fossil plants of the carboniferous system. This
belt of carboniferous strata, which I explored
and marked on the map of the province for
the first time in 1845, separates in its whole
length the granitic group from that next to
be described. (See Section, fig. 2.)
II. In the second, as in the first metamor-
phic group, the prevailing rocks are slate and
quartzite ; these are, however, of much more
varied characters. The former varies from
grey wacke to imperfect micaceous and talcose
schists through many intermediate varieties
of clay slate, and presents grey, olive, black
and reddish colours. The latter is of every
variety of texture, and ranges in colour from
white to dark grey. These rocks are also
more thinly bedded, and present more fre-
quent alternations than those of the granitic
group ; at some points they are observed to
pass into less altered rocks, contauiing organic
remains ; and in several locahties they are
traversed by metalhferous veins. The igneous
rocks which have penetrated the strata of this
group are very abundant, and exceedingly
varied in their composition and characters.
Their prevailing composition is felspatho-
homblendic, a character by which they are in
general markedly distmguished from those of
the granitic group. Syenite, greenstone of
many varieties, compact felspar, claystone,
and porphyries with bases of the two latter