Marcou.] 
60 
[Nov. 7, 
as Lower Calciferous. At that time Logan regarded the Quebec 
group as simply the homotaxis of the Chazy Limestone. 
logan’s classification of 1870. 
In the following “Report of Progress from 1866 to 1869 ” pub- 
lished in 1870, we have a remarkably detailed geological “map 
showing the distribution of the Lower Silurian rocks between the 
Chaudiere and Trois pistoles rivers, on the south side of the river 
St. Lawrence, province of Quebec,” by James Richardson. The 
celebrated Pointe Levis and all the country between the Chaudiere, 
the state of Maine, Madawasca and Trois pistoles are represented. 
The classification used is : 
Sillery division ^ 
Lauzon “ v Quebec group. 
Levis “ j 
Upper division } 
Middle “ r Potsdam group. 
Lower “ ' 
This geological map, so far as classification is concerned, is the 
most extraordinary imaginative map, on a tolerably large scale, 
ever published. The geographical distribution is made wholly 
without stratigraphic, paleontologic or lithologic facts to sustain it ; 
it is all imagination. If published fifty years ago, this map, would 
have been hardly acceptable. It is on a par with the “Geological 
map of the vicinity of Quebec ” by J. J. Bigsby (‘ Quart. Journ. 
Geol. Soc., Yol. ix, PI. vi, p. 82, London, 1853 ’) . However, Rich- 
ardson is less responsible for it, than Logan, who made the classi- 
fication and directed the whole work. 
Richardson says in speaking of some fossiliferous rocks of Bic 
harbor and other places : “ these rocks have heretofore been classed 
with those of the Quebec group, but they appear to underlie them 
unconformably, and being in some places marked by fossils which 
Mr. Billings considers to be of Potsdam age, they are now placed 
in the upper part of the Potsdam group. (Report of Mr. James 
Richardson, p. 120).” This new classification shows first that the 
original Quebec group of Logan, included the Georgia slates for- 
mation, for in these rocks at St. Denis, and Bic harbor, we have 
the fauna of the Georgia slates, viz. : Olenellus Thompsoni , Cono - 
coryphe , etc. ; and also at the same time we see that Billings has 
