Remarkable position of watershed. Blackwater Crossing. Cluscus Lakes. Terraces. 24 GEOLOGICAL SURVEY OF CANADA. and west, like the Blackwater Valley, but discharging its waters north- ward into the Nechacco. It is remarkable, that with the exception of the Black- water receives no important tributaries from the north, the surface of the Eu-chen-i-ko—which flows in a nearly parallel valley the plateau seeming, on the whole, to slope northward from the brink of its valley. This is specially noticeable in the lower part of its course, where streams eventually joining the Chilacco may be found almost within eunshot ofits northern edge. The northern and north-eastern side of Kuy- a-kuz Lake is bounded by the mountains of the Kuy-a-kuz Range, while the gently rolling plateau with sandy and stony soil, which separates it from the Blackwater, has an average altitude of about 3,700 feet. Country in the vicinity of the Trail and Location Line, westward by the Cluscus Lakes and Salmon River Valley to the Iltasyouco River.—The Blackwater is crossed at several places by the Indians when on the way to Cluscus Lakes, but of these the best known is at the junction of the Cluscus stream. At high water the river can only be crossed in this vicinity by rafting, but this is easily effected. The Cluscus stream was estimated on June 15th to have a width of twenty feet by two feet in depth and slope of about one in ten. Its water had a temperature of 61-5°, that of the Blackwater being 53:5°. The trail follows the stream southward for about half-a-mile, and then turns west- ward along the northern border of the lakes. The lower lake has an estimated total length of about six miles, with a width of less than half- a-mile at its upper end, and quite narrow and river-like at its lower. It is separated by a stream of about a mile and a-half in length from the upper lake, which, with a length of scarcely three miles, has a width of about three-quarters of a mile at its upper end, and holds two small islands. The water feeding these lakes must enter the upper on its southern side, and from its high temperature, is probably derived from other shallow lakes or extensive swamps. The country along the north side of the first lake is of very pleasing appearance, sloping gently with an undulating surface to the water, and dotted with groves of aspen and sprttce, where not covered with luxuriant. grass. ‘The northern slope of the upper lake is similar but steeper, and showing a smaller area of grazing land. ‘The lower lake stands about forty feet higher than the Blackwater River.