Granite.

Green schists.

Conglomer- ates.

Finlay River section.

26 c FINLAY AND OMENIGA RIVERS.

and are not distinguishable in the field from the massive diabases. They vary greatly in texture, passing gradually from a compact crypto- crystalline condition to a rock of medium grain.

At New Hogem the schists and diabase-tufis are replaced by a dark-coloured medium-grained granite, usually of a hornblendic type. An agglomeratic-looking rock, made up of granite and diabase débris, probably a junction material, was found in the wash of a small stream which enters the Omenica immediately below New Hogem.

Granite outcrops along the Omenica from New to Old Hogem, a distance of about eight miles, and extends north and south of the river in a direction parallel, or nearly so, to the prevalent strike of the neighbouring schistose rocks. The southern limit of the area was not ascertained, and it is possible that it may be continuous with the granite outcrops on Manson Creek.

From New Hogem the trail to Tacla Lake via Vital -and Tom’s Creek was followed. An occurrence of granite half a mile south of the river marks the western boundary of the granite area, as a short distance away, greenish schists and dark gray argillites similar to those on Germansen Creek crop out in the valley of Silver Creek. Outerops of the same argillites and schists occur in numerous exposures along the route traversed until within a few miles of Tacla Lake. They are instratified in places with grauwacke and beds of felsite. Hallaflinta and amphibolite are also not infrequent. The beds dip at high angles, usually towards the south-west, and are occasionally vertical. Seven miles from Tacla Lake, the argillites and associated rocks are replaced by conglomerates, sandstones and shales of a somewhat similar char- acter’to those on the Omenica above the Black Cafion. Conglomerates were also found on the shores of Tacla Luke, and they probably form the basement of the wide valley in which the lake is situated.

¢ The Tacla valley conglomerates are more indurated than those on the Omenica and have been subjected to greater disturbances, the tilting of the beds often amounting to 70° and over. The age of the conglomerates is doubtful, as no fossils were obtained from them, but they probably belong to the Cretaceous.

Finlay River Section.

The Finlay section is much inferior to that afforded by the Omenica, as the direction of the river for long distances is parallel or nearly so to the strike of the rocks. No exposures occur along the lower part of the river. From its mouth up to the Omenica, the Finlay winds