BouvA] 
218 
[April 17, 
ence to that “ On the Quebec Group in Geology” read before the 
Royal Society of Canada in 1882, and published in the first vol- 
ume of its Transactions. 
I have, however, no time for further discussion, and in any case 
I would probably not be able to convince Mr. Marcou that I can 
distinguish gneiss from quartzite, or that I am able to discern the 
evidence of a fault, or the difference between it and a landslide, or 
that the Levis beds are not older than the Potsdam. 
The completed map and report on the district which embraces 
the city of Quebec and the Island of Orleans will soon be ready 
for publication. These will give the final conclusions reached by 
this survey. 
They are based on the most recent and careful topographical 
measurements and stratigraphical field work and are supported by 
new, and in most cases abundant, palaeontological evidence show- 
ing the relative age of the various groups ; further that the Lau- 
zon and Sillery divisions of Logan are below and not above the 
Levis and represent some part of the Cambrian system, whether 
above or below the Potsdam cannot at present be determined. 
Had Mr. Marcou investigated the facts on the ground over the 
whole area as closely and carefully as I and my colleagues have 
done during the past twenty years, he would at least have some 
right to criticise our work ; and such criticism is always acceptable, 
and often valuable, but to criticise as Mr. Marcou does after very 
partial observations, and consequently, in ignorance of many most 
important facts, and entirely regardless of others, is, I think, mis- 
placed, and certainly affords no assistance in elucidating the geo- 
logical structure of such a complicated region as we have to deal 
with in the Province of Quebec. Neither do questions of nomen- 
clature and it is, therefore, useless to discuss these. 
General Meeting, April 17, 1889. 
The Vice President, Prof. Geo. L. Goodale, in the chair. 
The following papers were presented : 
INDIAN POT HOLES, OR GIANTS’ KETTLES OF FOR- 
EIGN WRITERS. 
BY T. T. BOUVfr. 
It is well known that wherever there exist waterfalls of any mag- 
nitude, pot holes, so called, are often found beneath the rushing 
