1895. ] NEW YORK ACADEMY OF SCIENCES. 191 
part of the Province still holds good. But it is evident from 
the tone of his writing that he considered the volcanic outbursts 
as of far later date than that now assigned to them, for he con- 
nects these disturbances with recorded earthquakes and changes 
of level in New Brunswick within historic times, and even pic- 
turés a number of supposed volcanic cones near Great Salmon 
River, east of Quaco.* 
In the Dominion Government Survey Reports, Dr. L. W. 
Bailey and G. F. Matthew recognize the existence of great 
amounts of volcanic ash, as well as massive lavas, porphyritic 
and vesicular. But the greater part of the series, consisting of 
fine-grained rocks denoted as felsite and petrosilex, remained to 
the last of doubtful origin, with an apparent tendency in Dr. 
Bailey’s later report (1877-8), written after a most careful and 
thorough study of the volcanic hills, to consider them as largely 
sedimentary rocks, though formed under special conditions of 
deposition ; + while Dr. Ells { considers them as volcanic. In 
his latest paper bearing on this subject § Dr. Bailey points out 
the need of microscopic sections of these rocks, both to make 
sure of their character and perhaps to determine also whether 
certain members are of pre-Cambrian age or are identical with 
very similar rocks of later origin. He summarizes the charac- 
ter and relations of the pre-Cambrian rocks as follows : 
“Among these Archean rocks at least two great groups of 
sediments are to be distinguished, which, in a general way, bear 
many features of resemblance to those which in other parts of 
Canada are known as the Laurentian and Huronian systems. 
At the same time it is impossible. . . not to see that . 
there are equally striking differences,. . . especially seen in 
the greater proportionate amount of distinctly stratified rocks, 
such as slates and quartzites, in the comparative absence of 
coarsely crystalline deposits of crystalline minerals and ore 
beds, and in the much greater regularity and uniformity of the 
whole. . . Another desideratum in connection with these 
two ancient systems is a better understanding of their time re- 
lations to each other, for though no doubt is entertained by the 
author as to the fact that the felsitic and schistose rocks refer- 
red to the Huronian are more recent than the granitoid and 
gneissic rocks and the great belts of crystalline limestone 
which have been regarded as Laurentian, a contrary view has 
* Report of 1840, p. 21. 
+ Can. Geol. Sur. Rep. 1877-8, p. 4, D. D. In a foot-note at this page, Dr. Selwyn 
compares this series to the ancient voleanic rocks of England and Wales, with which 
he believes they are identical in origin. 
tIb., p.3 D. 
2 Trans. Roy. Soc. Can., 1889, Vol. VII., Sec. 4, p. 3. 
