

CRETACEOUS AND TERTIARY—SOURIS RIVER. 87 
August, 1857, being induced to do so by the reports of Indians and half- 
breeds.* These remarkable rocks, which have long been objects of super- 
stition to the Indians inhabiting the surrounding country, owe their 
curious forms to the weathering away of a soft grey sandstone from be- 
low a bed of similar rock which weathers yellow, and is rendered durable 
by an abundant calcareous cement. Both the upper and lower sand- 
stones show false-bedded structure in great perfection; though that in the 
upper hard portion, is on a smaller scale, owing to the thinner divisional 
planes of the rock. The capping sandstone is not hardened in a perfectly 
uniform manner, but in belts several yards in width, lying parallel ina 
north-west and south-east direction, and separated by spaces more easy of 
disintegration. There is also a system of cross-jointing nearly at right 
angles to this main direction. 
205. This combination of structures has given rise, under the long 
continued action of the weather, to the remarkably castellated, fantastic 
and picturesque rock scenery of this part of the Souris Valley. The 
hard belts form tongues projecting diagonally from the grass-covered 
bank, and the erosion of the underlying soft sandstone, parallel to the 
cross joints, has, in several places, produced window-like openings 
through them. The soft rock bears in many places, rude Indian 
carvings, representing various animals and birds, strings of beads, &c. 
206. Short Creek, already mentioned as an affluent from the south, 
shows many sections of the lignite strata. The banks of the stream have 
assumed the most picturesque forms from successive landslips, and are 
often quite red in colour from the alteration of the clays by the burning of 
lignites. One of the most perfect sections is on the left bank, near the 
crossing place of the Commission Trail, and extends from the level of 
the prairie almost to the water of the stream. [Plate 4, Fig. 2.] 
FEET. IN 
Ry te ea ee ne eee 1 6 
2. Yellowish coherent sand, grey externally, and holding 
some much broken Unio-like shells at its base.......... 12 6 
I Ser Ae Ot Re Sas Mls editors Op ce oe sans 2 10 
4. Yellowish and greyish thin-bedded sands and sandy clays, 
with several very thin ironstone layers, weathering 
nrnnNnR St, fee AU eg oe es P20. 6 0 
I ie Ps aad denmens pe 2 4 
6. Similar to No. 4, with decayed fragments of gasteropodous 
| ee eee iiaelaiad Wise = a5 « obit eb » der » ap vigele 12 0 
7. Also similar to No. 4, but with a great number of thin 
eg a ee ne rrr re ry 3 0 
8. Hard yellowish sandy clay, a few inches at the top carbon- 
Me ete oe AS ee RT OO LOCOCO EL LOLOL 10 0 

* Exploration of British North America., pp. 49 and 225. 
