Foliation and Sedimentation — Lawson. 
173 
age is known to be intrusive is available here, and to the un¬ 
prejudiced mind its validity is at once apparent. 
The number of the gneissic sheets, their parallelism due to 
their penetrating along the lines of fission of the schists, and 
the sometimes slender partitions of schist between them, all of 
which are cited as arguments against the injected character of 
the gneissic sheets, have absolutely no weight in disproving 
their injected character. There is nothing in the conditions 
cited which is at all incompatible with a process of injection of 
a viscid magma within a shattered schistose rock under the 
great pressure which existed at such depths. 
6. Prof. W. says: “Fragments of gneiss very frequently 
occur in the schists. Hence the gneiss is older than the schists 
and could not have been injected into them.” This statement 
is of considerable importance, and I reserve any extended com¬ 
ment upon it till more fully informed as to the precise nature 
of the conditions alluded to. The identity of the fragments of 
the gneiss in the schist with the ordinary gneiss of the country 
should be established in order to make the argument effective; 
and then the question should be investigated as to whether the 
schists in question are really of Archaean age, or, as Irving con¬ 
ceived the Vermilion schists to be, of a later age, such as the 
equivalent of the Animikie, which is clearly post-Archaean. In 
the Huronian of lake Huron there are boulders of gneiss in the 
conglomerates but according to Irving the Huronian is post- 
Archaean. I have seen boulders of granite in the conglomerates 
of the schists of the region with which I am familiar, but none 
of gneiss; and have regarded them as probably derived from the 
floor upon which the upper Archaean rocks of the region were 
first laid down, but which by subsequent fusion and recrystal¬ 
lization gave rise to the Laurentian, which is so clearly newer 
than the upper Archaean though underlying it. Included 
boulders or pebbles of gneiss might have a similar origin, and 
if proved to exist in the upper Archaean, through which the 
Laurentian is intrusive, we would be forced to assign some such 
origin to them. 
7. Prof. W. says : “ The gneissic fragments in the overlying 
schist have their planes of foliation in all positions regardless 
of the bedding of the schist. If the schistic bedding controlled 
the foliation of the gneiss immediately below it would be able 
to control that of the gneiss bodily enclosed.” 
