92 B. N. A. BOUNDARY COMMISSION. 
* 
217. On the opposite side of the river valley, near this place, the 
upper part of the bank shows a good section of arenaceous clay, below 
which, and some fifteen or twenty feet below the prairie level, is a _ 
seam of lignite of good quality, four feet in thickness. This lignite bed 
would seem to occupy a position stratigraphically superior to the last. 
218. Somewhat further up the stream, and on the same side of the 
valley, about sixty feet below the prairie level, and sixteen feet above 
the river, a bed of lignite occurs, of which the upper three feet only are 
visible. The bank above it is not well exposed, but appears to consist of 
sandy clays. The lignite is of good quality, but much weathered at the 
out-crop. It may very probably represent the continuation of that of the 
last section. 
219. The whole of these deposits, though in some places showing a 
dip amounting to a few degrees in one direction or other, appear to have 
no determinate direction of inclination, but over large areas to be as 
nearly as possible horizontal. 
Gap in the Section on the Boundary-line. 
220. West of Wood End, the Souris Valley runs north-westward 
along the base of the Coteau, diverging rapidly from the Boundary-line. 
It loses, at the same time, its abrupt character, and no sections either of 
Tertiary or Cretaceous rocks occur on it for a long distance. In follow- 
ing the forty-ninth parallel, the’ escarpment of the third great prairie 
level is overcome, and it is not till after having passed through the bro- 
ken Coteau belt, and reached the Great Valley, that exposures of the 
underlying rocks are again found. This valley is the most eastern great 
channel of erosion which crosses the Line southward, towards the Mis- 
souri, and in it the beds of the Lignite Tertiary are exhibited on a grand 
scale. On the Boundary-line, thus, a space of eighty-two miles from the 
263 to the 345 mile point, is completely shrouded by drift deposits. 
There is every reason to believe, however, that the Lignite Tertiary 
beds stretch uninterruptedly between the two localities, and an exposure 
of these rocks, some distance north of the Line, helps to sustain this 
view. 
221. This small exposure of the Lignite Tertiary was discovered ata 
locality on the meridian of the 307 mile point, but nearly twenty miles 
north of the Line; where the Trader’s Road to Wood Mountain, in going 
westward, crosses the Souris for the second time. Of the rocks at this 
place a very small section is seen, but sufficient to correlate them with 


