AGE OF THE KILLARNEY GRANITE. 
11 
Similar relations between the Bruce series and a granite 
like that at Killarney were afterwards observed among the islands 
in the North channel. The small islands near shore, from 
south of Lake Lacloche to near Aird island, are part of an east- 
west belt of the Bruce series. All the formations in the series 
are represented. The quartzite dyke shown in Plate I was 
observed on an islet directly south of the outlet of Lacloche lake. 
The relationship of the series to the neighbouring granite can be 
seen on Fox island, along the north shore of which the granite 
intrudes quartzite, sending irregular apophyses into it and alter- 
ing it locally to a spotted quartzite. 
THE KILLARNEY GRANITE. 
Comparatively little is yet known about the extent, mode of 
intrusion, and petrological nature of the Killarney granite. 
Barlow 1 traced the contact of granite and gneiss with the Pre- 
Cambrian sediments from Killarney eastward to near Wanapitei, 
but he did not distinguish the granite from the gneiss, which 
is probably not of the same age. Bell 2 mapped the Killarney 
granite among the islands of Lake Huron. To this work is 
added the writer’s observations in 1915. 
At Killarney, the granite is a rather coarse-grained, light 
red rock, apparently without gneissic foliation. Its contact 
edges are not fine-grained. Salmon-red feldspar is the chief 
constituent. Quartz is so subordinate in quantity that the rock 
approaches a syenite in composition. The dark mineral is 
biotite. The granite seen on Fox and adjoining islands is of the 
same description. 
The granite at Cutler is different in appearance from 
that at Killarney and Fox island and may be an intrusive distinct 
from it. It is a medium-grained grey granite composed of 
white feldspar, quartz, and both dark and light varieties of mica. 
Like the Killarney granite it shows no gneissic structure. It is 
intersected abundantly by dykes of pegmatite consisting of 
quartz, feldspar, and muscovite, the latter occasionally in 
1 Relations of the Laurentian and Huroman rocks north of Lake Huron: 
Bull. G.S.A., Vol. IV, pp, 313-332. 
2 Rept. of Progress, G.S.C., 1876-77. 
