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have not become gneissose, and were much more brittle than the rela- 
tively plastic granite gneisses in which they flowed. 
A minor occurrence of very acid gneissic red granite, consisting 
dominantly of potash feldspar and quartz, was found to contain nodules 
and small vein-like masses of zonally arranged quartz sillimanite and 
tourmaline, which are regarded by the authors as acid differentiates 
and not as inclusions. 
The alignment of the granite gneiss batholiths with the major axis 
of folding, and the parallelism of the foliation and folding of both sedi- 
ments and intrusions, indicates that the invasion of the granite gneisses 
and the deformation of the region was largely contemporaneous. Intru- 
sion was effected by the up-bowing of the sediments, and by the invasion 
of the magma as a pegmatitic facies into the shattered sedimentary 
border zone, or by /it-par-lit intrusion, followed by the stopping-off of the 
intruded rocks into the magma. Solution of the sediments was a very 
subordinate process. 
The authors believe that the granite gneisses were in a partially 
crystallized but pasty condition when injected, as shown by their flow 
lines, the granulation of the feldspars, and the elongation of the more 
plastic quartz crystals. While most of the deformation of the granite 
gneisses took place without fracturing, other than the granulation of 
mineral particles, some of the sharp folds grade into faults, or shear 
zones which are invariably filled with granite pegmatite. Many of the 
granite pegmatitic veins in shear zones and in the border zones of the 
sediments were intruded before deformation was completed, and became 
granulated and sheared into pseudoconglomerates, while others were 
injected after deformation was completed and show no fracture or 
distortion. 
The principal exploited economic mineral of these areas is corundum 
from the syenites. Gold and copper-bearing veins are also known to 
dissect the amphibolites, while magnetite is found as a segregation in the 
syenites and in bands in the stratified amphibolites. Apatite and 
graphite-bearing pegmatites cut the limestones, and graphite also occurs 
in lenses parallel with the stratification of the limestones. Post- 
glacial deposits of marl and ochre have been located, and building 
stones in the form of marble, serpentine marble, and sodalite are described 
as valuable but as yet undeveloped resources. 
This report is rich in illustrative and descriptive information on the 
mechanics of intrusion, the adjustment of materials to stress strain 
conditions, magmatic differentiation, and on contact metamorphism. 
If anything, it may be mildly criticized for too much detail. In order 
