﻿260 Frof. Milne and Alex. Mvrray — Roeks of Newfoundland. 



degradation have washed away portions of these rocks and divided 

 them in patches ; whilst metamorphic action has so changed their 

 character that at times they are hardly to be recognized. 



Sillery (^St. Julien Sandstones, etc.)^ — Above the serpentinons and 

 Magnesian series, which has been estimated by Mr. Murray as having 

 a thickness of from 16 to 1700 feet, there is a large series, chiefly 

 composed of black slates and limestones, approximately 3 to 4000 

 feet in thickness. In these slates, which are well exposed in the 

 northern parts of the island, I have observed both intrusive and 

 imbedded masses of diorite. They are generally of a dark grey or 

 greyish green colour, and in some cases amygdaloidal, the amygdules 

 being filled with calcite. Under the microscope, altered felspar, 

 hornblende and grains of magnetite are generally to be seen. 



In Noddy Bay these shales are serpentinous, and contain im- 

 bedded nodular masses, which under the microscojoe resolve them- 

 selves into a sei'pentinized diorite. True serpentine is also to be met 

 with in the same locality. The intrusive rocks of this district would 

 show that the volcanic action continued after the deposition of the 

 upper part of the Quebec Group. 



Niagara and Clinton.' — The only display of these rocks which has 

 been hitherto recognized is to be found at the head of White Bajf, 

 where we have a series of conglomerate, and slates capped with 

 Limestone, altogether 2800 feet in thickness. Owing to the oc- 

 currence of a series of faults, some of which may amount to 1000 

 feet, there has been difficulty in tracing out the sequence amongst 

 the members of this formation. Traversing these rocks there are 

 several large dykes of melaphyre and felsite. One of these latter, 

 at the S.W, end of Sops Island, appears in columnar masses 40 — 60 

 feet in height. They are of a pinkish colour, and have a splintery 

 coarse fracture. Their measurements are about 1 foot in diameter, 

 and 20 feet in length. They have generally from 4 to 6 sides. 

 In places they are curved and slightly divergent. The tops of these 

 prismatic-like columns form acute angles with the sides, instead of 

 being at right angles, as is so generally the case. Between these 

 columns strips of greenstone, which under the microscope resolves 

 itself into a melaphyre, may be seen. These felsites are also to 

 be seen further to the north. 



On the S.E. side of the island there is a large dyke, which also 

 appears to be a melaphyre, and probably derived from the alteration 

 of a dolerite. It contains many veins of calcite and quartz, and 

 along one side of it a very fair deposit of galena. 



1 In the note on page 256 I have already expressed my views regarding the strati- 

 graphical position of these sandstunes. 1 \v\-ve visited St. Juliens myself, and Mr. James 

 Richardson, of the Ge()h)gical Survey of Canada, visited the place where the formation 

 is largely displayed, at the north-eastern termination of the island; but a contact with 

 the sei'pentinous group was not seen in either case ; and 1 hold to the opinion that it 

 is in consequence of the later group being unconformably spread over the older rocks, 

 that the saudstones are not seen at How Harbour or at Pistolet Bay. — A.M. 



^ Rocks of Middle Silurian age have already been referred to, as having a wide 

 spread in Exploits Bay and the southern parts of Notre Dame Bay. The lithological 

 characters, and some few obscure fossils, also seem to indicate that the series, or a 

 portion of it, extends far up the Exploits and the Gander Eivers. — A.M. 



