108 B. N. A. BOUNDARY COMMISSION. 
bedding. It crumbles down into earthy banks, which, however, in some 
places, exhibit prominent nodular bands of ironstone, and in connection 
with these the fossils are, for the most part preserved. They are usually 
completely imbedded in the ironstone and filled with it, though the | 
concretions must have been formed some time after the deposit of the 
clay, as the larger shells are frequently crushed. The Baculites still 
retain to a great extent, their original nacreous lustre and play of colour. 
The ironstone nodules are often septarian, and from the rapid removal of 
the clays by denudation, their fragments strew the surface in abundance. 
selenite is diffused in small quantity through all parts of the beds. 
265. Taking into account the difference of level between this 
locality and that of the section in the Bad Lands, the clays here seen 
must be at least 200 feet below the base of division y. The sombre 
Cretaceous clays of these localities resemble a good deal in lithological 
character the beds of the Pembina Mountain group, and they also hold 
the same relation to the overlying Lignite Tertiary series, as that assigned 
to those deposits. They differ chiefly in being less consolidated and 
darker in colour, and in forming when weathered a crumbling bank of 
earthy appearance, rather than one of somewhat sharp-angled shaly 
fragments. The scarcity of fossils in the Pembina Mountain sections, 
prevents any instructive paleontological comparison of these beds with 
them. It must be remembered too, that probably at least several 
hundred feet of the upper part of the Pembina Mountain group, was no 
seen on the eastern margin of the basin, and it is this very part of the 
series which must be represented here. Taking into account, however, 
the great distance separating the exposures on the eastern and western 
margins of the region covered by Tertiary, the lithological and structural 
resemblance of the deposits is quite as close as could be looked for, even 
in an area characterized by such wide-spread similar conditions, as the 
interior plateau of the continent. 
266. Westward from these sections, the continuity of the Cretaceous 
clays in the vicinity of the Boundary-line, is indicated by occassional 
small exposures, and at a distance of thirteen miles, a tolerably good 
exhibition of the rocks again occurs. They are now found to resemble 
very closely the clay-shales of the upper part of the Pembina Mountain 
series, and to differ to a corresponding extent from those last de- 
scribed. They are firmer in texture, and lighter in colour, and are 
traversed in all directions by rusty-faced cracks. The peculiar 
small rusty fucoidal markings, already more than once referred to, 

