The accompanying section (Plate XXII) will serve to show, diagrammatically (after Dr. Ami), the succession of the Cambrian rocks at Mount Stephen and Mount Field, B.C., and the position of the Trilobite bed on the flanks of Mount Stephen (referred to on p. 503) from which Mr. Whymper's collection was obtained.

The Canada Pacific Railway crosses the watershed of the Rocky Mountains at Hector or, as it is sometimes called, Kicking Horse Pass, and the specimens brought back by Mr. Whymper represent a district extending for some twenty miles on each side of the track, either on or west of the divide. The first group was obtained from summits lying near the railway on its southern side. Of these Mount Whyte is about three miles from it on the divide, which is crossed by Pope's Col just to the north of that summit, and about a mile to the north-east of the latter rises Mount St. Piran. About 3½ miles south of Mount Whyte, Mitre Col leads from the Lefroy to the Horseshoe glacier, between Mount Lefroy, which is on the divide, and Mitre Peak on the eastern side of it.

The August number of the Quaterly Journal of the Geological Society contains a paper on this subject by Dr. J. W. Spencer, who believes that the rocks which were described by us under the head of ‘Raised Coral Reefs’ do not form one continuous succession of Pleistocene reef-rocks, but consist of several different limestone formations. He thinks that there are three such formations, and that each is separated from the other by a break or unconformity.

Nearly ten years ago I proposed the term ‘hemera.’ The term is coming into use; but, so far as I am aware, in the majority of cases it is greatly misunderstood. From this cause arise objections as to its use, such objections being based on the misconception that the hemera is a subdivision of a zone. It is nothing of the kind.