2 
MUSEUM BULLETIN NO. 3. 
from other workers in equivalent strata. Throughout the entire 
study of the collections the writer has had the critical advice of 
Professor Charles Schuchert and the generous co-operation of 
the officers and scientists of the Geological Survey of Canada. 
Doctor R. S. Bassier assumed the study of the bryozoa and 
ostracoda and the identifications of all such species are his. A 
large number of other scientists have given advice and assistance. 
To them acknowledgment will be made in the final publication. 
The study of the Anticosti faunas and the section have devel- 
oped five facts of importance. They are as follows: (1) Bil- 
lings’ statement that the section is complete from base to sum- 
mit and contains no stratigraphic break is sustained; (2) many 
of the species have ranges through greater thicknesses than the 
same species have in other regions; (3) the faunas of the north 
and south shores show great differences which in every 
instance correspond to differences in lithology and hence 
to differences in the ecologic conditions at the time of sedimenta- 
tion; (4) the section is much thicker on the north shore than on 
the south, contains fewer corals and no coral reefs, and the sedi- 
ments are less calcareous, but far more shaly and sandy; (5) the 
rocks of the Anticosti section once extended far inland on the 
Laurentides and much higher rock once overlay the highest 
rocks now present. 
The absence of stratigraphic breaks in part explains the long 
vertical ranges of many of the species, since they occur in the 
strata which are wanting in equivalent sections of other regions. 
While the faunas of the north and south shores are markedly 
different in many of the zones, it is also true that they are almost 
absolutely identical in those zones wherein the sediments of both 
shores are the same. These faunal differences are rendered more 
conspicuous by the absence on one shore of species to which 
great diagnostic value has been given, but which are present on 
the other shore. One of the most striking examples of this fact 
is the presence of Rhynchotrema perlumellosa in great abundance 
and with a considerable range in the northern outcrops of the 
Charleton formation, while to date no collector has obtained a 
single specimen of this species from the south shore, although the 
equivalent beds are most certainly exposed and less than twenty 
