. Relics of primeval life, beginning of life in the dawn of geological time. dland, etc., the beds have beenconsiderably altered, and are locally more mixedwith igneous products. The physical picture pre- ^ Dr. G. M. Dawson, , the present Director of the Geo-logical Survey of Canada, whose judgment in this matter shouldbe of the highest value, holds that the original simple arrange-ment of Logan still holds, notwithstanding the multitude ofnew names proposed by the Western Geologists of the UnitedStates. 2 Van Hise, Pre-Cambrian Rocks of North RenduSy 5th Session Internat
. Relics of primeval life, beginning of life in the dawn of geological time. dland, etc., the beds have beenconsiderably altered, and are locally more mixedwith igneous products. The physical picture pre- ^ Dr. G. M. Dawson, , the present Director of the Geo-logical Survey of Canada, whose judgment in this matter shouldbe of the highest value, holds that the original simple arrange-ment of Logan still holds, notwithstanding the multitude ofnew names proposed by the Western Geologists of the UnitedStates. 2 Van Hise, Pre-Cambrian Rocks of North RenduSy 5th Session International Geol. CongressJ891, p. 134. Also Report Geol. Survey, 1895. PRE-CAMBRIAN LIFE 67 sented to us by the Huronian is that of a shoredeposit, formed under circumstances in which bedsof pebbles and sand were intermixed with the pro-ducts of neighbouring volcanoes. Such a formationis not likely to afford fossils in any considerablenumber and variety, even if deposited at a time of iil|ll,;* TW imsm i« ^!. : i[!fi| m -^ Will -1«1; m riji:Ii:;|i,ii{,! W : : __;_J. Fig. 15.—Annelid Burrows^ Hastings Series, Madoc, I. Transverse section of Worm-burrow — magnified, as a transparent object.(«) Calcareo-silicious rock. (/) Spacefilled with calcareous spar, (r) Sand agglut-inated and stained black. (d\ Sand less agglutinated and uncoloured. 2. Trans-verse section of IVorm-burrow on weathered surface, natural size. 3. The same,magnified. abundant marine life. It is therefore not wonderfulthat we find little evidence of living beings in theHuronian. In Canada I can point to nothing ofthis kind, except a few cylindrical burrows, pro-bably of worms (Fig. 15), and spicules possibly ofsilicious sponges, which occur in nodules of chertin the limestones, traces of laminated forms like 68 RELICS OF PRIMEVAL LIFE Cryptozoon or Eozoon (Fig. 17), and minute car-bonaceous fragments which may be debris of sea-weeds or Zoophytes. In rocks of similar age in theUnited States, Gresley ha
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