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PKOCEEDINGS OP THE GEOLOGICAL SOCIETY. 



especially upon stratigraphical geology as based upon the range and 

 distribution of organic remains, phenomena which since the time of 

 William Smith have been studiously kept in mind, teaching us the 

 succession of life and the relation in time of one formation to 

 another — each successive sedimentary group containing undoubted 

 records of its life and deposition, thus rendering clear and definite the 

 changes in, and the advance of life through time. 



~No more difficult problem exists or remains to be solved than the 

 first appearance or commencement of life on the globe. Is the Lau- 

 rentian of Worth America, with its one known solitary form of life, 

 the oldest sedimentary rock existing ? is Eozoon canadense the oldest 

 form of life ? Research up to the present time has not revealed to us 

 one of higher antiquity ; neither has it even a truly associated form. 

 ISTo true Annelide, Plant, or Protozoon accompanies this still mys- 

 terious progenitor of Palaeozoic life. 



The Eozoic or Laurentian gneiss of Britain or Europe, has not yet 

 yielded a semblance of any thing approaching Protozoic affinities, 

 although in the Hebrides, Norway, Sweden, Bohemia, and Bavaria 

 the Laurentian rocks have been recognized. 



That the Laurentian rocks are not the oldest is manifest ; others 

 of infinitely greater age yielded sediment to the Laurentian sea, 

 and pabulum for the sustenance and material for the shelly structure 

 of its supposed only inhabitant; but whether Eozoon had precursors 

 or not, time will probably tell. 



Dr. Dawson, however, suggests that vegetable life preceded 

 Eozoon, and may thus have accumulated previous stores of organic 

 matter. If any older forms of animal life did exist, they cannot 

 have belonged to much simpler types ; " naked Protozoa would 

 have left no sign of their existence, except probably minute traces 

 of carbonaceous matter." Dr. Dawson in the year 1865 discussed 

 the question of associated organic structures, and what share, if 

 any, they may have had in the accumulation of the Laurentian 

 Limestone. Microscopic examination exhibited evidence of calca- 

 reous and carbonaceous fragments of organic origin. The contents 

 of the organic limestone, as shown by Dr. Dawson, were " Remains 

 of Eozoon, other calcareous bodies probably organic, objects im- 

 bedded in the serpentine, carbonaceous matters, perforations or 

 worm-burrows." Dr. Dawson strongly and fairly argues for asso- 

 ciated life. 



The presence of graphite in large deposits occurring both in 

 beds and veins in the Laurentian rocks, clearly determines that its 

 origin and deposition were contemporaneous with the mass or con- 

 taining rock ; the graphite, again, is associated with calcite, quartz, 

 and orthoclase. It is not improbable that the " vein graphite " was 

 introduced as a liquid hydrocarbon. Dr. Sterry Hunt believes it 

 possible that it may have been produced in a state of aqueous solu- 

 tion*. In the lower Laurentians the quantity is enormous. Dr. 

 Hunt also believes that the origin of the graphite was due to the 

 deoxidation of carbonic acid by living plants. That the graphitic 

 * Hunt, Report of the Geological Survey of Canada, 1866. 



