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THE DISTRIBUTION OF ANCIENT VOLCANIC ROCKS.
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retarding effect on the deciphering of New Brunswick geology. Numerous occurrences of felsite, porphyries and amygdaloids were described between Musquosh Harbor and Loch Lomond, near the city of St. Johns, and along the line between Kings and Queens counties (Coldbrook and Bloomsbury groups). Similar rocks were traced from L'Etang Harbor, near Passamaquoddy Bay, along the edge of the Bay of Fundy to Shepody, in Albert County (Coastal group); and finally, a belt of analogous composition was described between the Long Reach of the St. Johns river and Mace's bay (Kingston group). These rocks were at this time, however, on account of Hunt's influence, united with their associated sediments, and nothing is said about their volcanic character. These authors were forced to regard similar rocks on the shores of Passamaquoddy bay as Silurian, because of associated fossils, in spite of their lithological identity with the "Huronian." These they called the Mascarene series.[1]

Four years later the same authors united the Kingston and Mascarene groups and regarded both as upper Silurian.[2] In a report of the pre-Silurian rocks of Albert, eastern Kings, and St. Johns counties, Ells gives some clear statements relative to the volcanic rocks of southern New Brunswick. He says:

"In their lithological aspect, the rocks forming the southern metamorphic belt present great diversity. Their general character is of two kinds—altered sedimentary and volcanic.***In the latter we include the great mass of petrosiliceous rocks, so called, with breccias and other ash rocks, which in places show bedding, but this is often so obscurely marked as to be exceedingly doubtful.***Near the contact of the volcanic and sedimentary rocks we find an extraordinary development of generally coarsely crystalline diorites and syenites, which would seem to form the basal portion of the volcanic part of the series."[3]

A report on the same rocks was published at the same time by Bailey, who divides them in to a feldspathic, syenetic and gneissic group, including limestones, serpentines, and dolomites

  1. ↑ Ib., pp. 144-158.
  2. ↑ Ib., 1874-75, pp. 85-89.
  3. ↑ Ib., 1877-78, D. p. 3.
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