Robert Chalmers—Glaciation of E. Canada. 211 
But the larger shells, which by Billings, Walcott, and the writer 
have been referred to Stenotheca, are Gasteropods allied to Metoptoma. 
They are not, however, of this genus, which has been described as 
having a truncated apex, whereas the beak of the Cambrian shells 
is arched and acuminate at the apex. 
The minute shells, of which 8. concentrica is the type, and which 
alone are properly of the genus Stenotheca, show, when magnified, 
a chasing of waving or chevron lines visible both on the outside and 
inside of the crust, and these lines are much more distinct on the inside. 
There is no suture along the back, the folded carapace having been 
irregularly cracked where the sides have been crushed together in 
the shale. No nuchal piece has been observed, so it appears to have 
had a minute carapace of one piece only. These fossils are not 
_ very plentiful, but occasionally they are found in considerable numbers 
on layers of the fine dark shales which are equivalent to the Menevian 
shales of St. David’s in Wales. 
St. Joun, N.B., Canapa. 
VI.—Gutactation oF Hastern CAanabDa. 
By Rozert Cuaumers, Esq., 
Of the Canadian Geological Survey. 
PAPER on the Glaciation of Hastern Canada by the writer 
will shortly appear in the Canadian Record of Science, 
Montreal. It is intended to be a condensed statement of the 
principal facts hitherto collected on this interesting subject, with 
references to the reports and publications in which details are given. 
The following is an abstract which I send to the GronocicaL 
Macazine in advance. The subject is regarded as an important 
one, and has occupied the attention of geologists for many years, as 
Eastern Canada is the battle ground, so to speak, of the advocates 
of the rival theories of continental glaciation and floating ice. The 
results thus far obtained from a somewhat careful study of its 
glacial phenomena, however, point to conclusions which are at 
variance with those held by extreme glacialists, and show that the 
theory of local glaciers upon the more elevated portions of the 
country and icebergs or floating ice striating the lower coastal areas 
during the Post-Tertiary submergence of these, as maintained by 
Sir William Dawson, will serve to explain all the observed 
phenomena. The term ‘local glacier’ I define as an ice-sheet 
limited in extent, that is, confined to one valley or hydrographic 
basin, whether large or small, and influenced in its movements by 
local topographic features, such as mountains, water-sheds, hills, or 
the valleys of the larger rivers. The data have been collected 
chiefly by the staff of the Geological Survey; but Sir William 
Dawson, who has long studied this region, and others have done 
much valuable work in glacial geology here.. 
In reference to the origin and movements of local glaciers, it may 
be stated, that the main facts pertaining to each centre of dispersion, 
when correlated, show that these glaciers were independent bodies 
