27 
In the following section only that part of “Ottawa section” 
is taken which corresponds to the “Rockland section” in order 
to make a comparison in the study of the range of species in the 
upper Black River and lower Trenton. 
Section 3 Miles East of Ottawa 1 
Ft. In. 
7. Coarse-grained limestone, irregular fracture. Dove-tinted in 
colour. Fossils present in the upper layers, but scarce else- 
where. The lower beds of this exposure appear to overlap 
those of 5 and 6 15 6 
6. Thiele layers of coarse-grained limestone with irregular fracture. 
Dove-tinted in colour weathering grey. Fossils few 7 6 
Bed disturbed by a local fault. 
5. Coarse-grained limestone interbedded with more shaly layers. 
Weathering rubbly. Fossiliferous 5 6 
Beds disturbed by a local fault. 
Base of Trenton exposed here. 
Covered, in field 2 ± 
4. Grey limestone. Finer in texture than above 5 0 
Covered 2 0 
3. Grey limestone, weathering shaly. Very fossiliferous 4 6 
Covered 1 6 
2. Grey limestone weathering rubbly containing numerous cephalo- 
pods 5 4 
Base of the Leray beds of the Black River. 
1. Massive bed of fine-grained, light-grey limestone capped by 
1 ft. 6 in. layer almost solid Tetradium cellulosum 5 4 
Covered 2 0 
la. Thin-bedded layers of light-grey limestone, full of gastropods, 
etc 2 0 
Base of Lowville exposed 
Total 58 ± 
Tor details of location see page 21. 
