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388 Canadian Record of Science. 
through the Paleozoic Period. In Canada they extend in 
patches along the coast line of the old Laurentian continent 
and stretch inward into its bays and inlets. The account 
given of them by Logan and Murray in the Geology of 
Canada under the names Lower and Upper copper-bearing 
series is in many respects the best up to the present time, ° 
as I can testify from personal examination of portions of 
the ground. 
It may be remarked here that in Canada, though the 
Laurentian beds are much folded and contorted, they are 
comparatively little affected by faults or over-thrusts ; and 
the succession is often extremely clear, while the outcrops 
of individual beds can be traced over great distances. This 
applies especially to the Upper or Grenville series, holding 
the great limestones and beds of graphite and magnetite, 
and the serpentinous limestone containing Hozoon. 
The simple arrangement of the infra Cambrian rocks 
as Kewenian, Huronian and Laurentian is further vin- 
dicated by Walcott’s section in the Colurado Canyon, which 
shows only these superimposed but unconformable. The 
lowest member is a granitic rock probably equivalent to 
the Fundamental Gneiss. Walcott has found in the upper 
part of the infra Cambrian an obscure Discina-like or 
Stenotheca-like shell and a fragment resembling the cheek 
of a small Trilobite. Still lower are the stromatoporoid 
masses of supposed Cryptozoum. Some specimens of this 
recently sliced show distinct traces of structure similar to 
that of Hall’s typical species of Cryptozoum. 
In the second number of the “ Journal of Geology,” Van 
Hise sums up what is known of the older rocks of Lake 
Superior and divides them into what he calls “ Basement 
Complex,” equivalent to the Lower Laurentian of Logan, 
Lower Huronian and Kewenian. In this he agrees per- 
fectly with the original classification of Logan and Murray 
in the Geology of Canada, 1863, except that possibly some 
Upper Laurentian rocks are included in the “ Lower 
Huronian.” The true Upper Laurentian or Grenville 
series seems, however, to be absent in the Lake Superior 
