204 TRANSACTIONS OF THE [aPR. 15, 
SopA-GRANITE. Pl. XVI. and XVII. 
A high ridge stretching from Hardingville on the Germaine 
Brook to the great bend in the Hammond River below Upham 
consists of a red granitic rock called syenite (hornbende-granite) 
by the Survey officers, but which on microscopic study appears 
to be an augite-soda-granite. The Germaine Brook and Ham- 
mond River run at the foot of its steep eastern slope; on the 
other side lies a broken country, little opened up. The rock 
was considered by Prof. Bailey as an extremely metamorphosed 
phase of the breccias and felsites which surround it; and he cites 
instances of the transition of the one into the other, which the 
writer has not yet been able to completely follow. * 
In regard to Prof. Bailey’s conclusion, it must be observed 
that microscope sections have failed to show any extreme meta- 
morphism in the Coldbrook or Coastal groups. They have fre- 
quently a secondary cleavage developed, which often amounts 
to an imperfect schistosity. But of the entire re-formation of 
the minerals in the rock so as to make a gneiss, still less a gran- 
ite, I have seen no instance in the post-Laurentian rocks of this 
region. Ii the rock is not a subsequent intrusion, the view of 
Dr. Ells, stated with regard to a number of such areas of crys- 
talline rocks occurring near the borders of the volcanic areas, 
seems more acceptable. + He regards them as being basal parts 
of volcanic flows, their crystalline character being due to slow 
cooling. 
Prof. Bailey describes the passage from felsite into “ syenite,” 
as follows: 
“With the dark grey petrosilex are irregular beds of pale red 
and red felsite, which in approaching Titus’ Mill become at the 
same time more frequent and more crystalline. In some por- 
tions .. . a distinct but usually highly contorted stratification 
is discernible, but other portions are quite homogeneous, and by 
admixture of a dark green mineral resembling hornblende be- 
come imperfect syenites. . . . It is supposed that these syenitic 
hills ... are simply the petrosilex and breccia in a more 
altered form. That they are in great part of fragmentary ori- 
gin is very evident, and even where apparently most crystalline 
a rounding of the grains of quartz, and the occurrence of irreg- 
ular cavities or vesicles suggests that all have been produced by 
like agencies.” { 
The microscopic appearance of the ‘“ syenite ” throws consid- 
* Geol. Sur. Can. Rep., 1877-78, p. 8, DD. 
+ Geol. Sur. Can. Rep., 1877-78, p. 3, D. 
t Loe. cit. 
