EXPLANATIONS OF THE SECTIONS TO ILLUSTRATE JULES 
MARCOU’S PAPER ON THE “GEOLOGY OF THE 
ENVIRONS OF QUEBEC.” PLATES VIII AND IX. 
Fig. No. 1. Section of Montmorency’s fall. a. Black River limestone. 
b. Lower Trenton limestone The strata between the quartzites at the 
foot of the fall and the river St. Lawrence are gray and black slates with 
beds of calcareous marl of the City of Quebec or Swanton group of the 
Upper Taconic, August, 1868. 
Fig. No. 2. Section of Montmorency’s fall, by Alfred R. C. Selwyn, 
June, 1884. 
Fig. No. 3. Section from the Ravine on the east bank of Mont- 
morency’s fall to the River St. Lawrence, a. Black River limestone or 
Lower Trenton. Dip 5° southeast and almost horizontal at the summit 
of the fall. B. Upper Trenton and Lower Utica, composed of 20 feet of 
Upper Trenton limestone at the foot of the ravine; then 16 feet of gray 
slates; then 2 feet of limestone; then 35 feet of brown and gray slates. 
These 73 feet of strata have fallen into the ravine by a landslide. At the 
contact between the brown slates of the Utica and the black slates of the 
City of Quebec groups there is a great disorder and a confused stratification ; 
some of the slates being verticales an.) even reversed dipping westward 
instead of eastward. C. Black and gray slates of the City of Quebec or 
Swanton slates. B ' . A tongue of Upper Utica slates at the St. Lawrence 
river shore ; another reiuain of a landslide. 
Fig. No. 4. Interrupted section taken on the Charles River banks, from 
the village of Indian Lorette down the rapids, showing the inclination of 
the Calciferous, Black River and Trenton groups of strata by landslides. 
Fig. No. 5. Arched fold with a long rise of the strata at the base of 
the Citadel of Quebec, in following Champlain Street. 
Fig. No. 6. Section from Montmorency to the mouths of Beauport 
and St. Charles Rivers across the city and Citadel of Quebec to the 
western foot of the Citadel. 
Fig. No. 7. Section from the St. Lawrence River, at the Point Levis 
shoal to the St. Joseph’s church and the Redoubt. The magnesian lime- 
stone of the Redoubt contains a Primordial fauna, and in following it after 
the fold of that lenticular mass; just near the Letellier house, a Trinu- 
cleus has been found with a Dikelocephalus in the same piece of limestone. 
