24 KOY A i. SOCI i:i Y ( » F C A N A I ) A 



In the report for the next year this opinion as to the relative position 

 of these divisions is maintained; and in tlie working out of the district 

 to the north and east of the original area in Hastings county the several 

 kinds of gneiss and limestones were arranged in various groups, of 

 whieli, in 1875, he concludes that tlie relations are very uncertain, but 

 expresses the conviction that the scliists and dolomites of the Hastings 

 series are very similar to certain portions of the Huronian of Logan, and 

 to the crystalline series of the eastern townships of Quebec, usually 

 styled the metamorpliic portion of the Quebec group. 



In the report for 1876-77, Vennor, having in the meantime reached 

 and crossed the Ottawa River, and connected the rocks of the Hastings 

 with those styled by Logan tlie Grenville series, sums up all the evidence 

 bearing on the relations of the different members of the crystallines; and 

 as a result divides them into two great series, viz., a great gneiss and 

 syenite portion without limestones, representing the oldest division, the 

 equivalent of the Fundamental gneiss, and a thinner gneissic and 

 schist series, witli limestones and with large areas of labradorite rocks. 

 These are overlain by the lower Silurian formations, ranging from the 

 Potsdam to the Trenton. 



In the final summing up of Vennor two elements evidently inter- 

 fered with the enunciation of the relationship which he supposed to 

 exist up to or near the date of his last report. Of these one was the placing 

 of the anorthosites at the summit of the Laurentian years before, on the 

 hypothesis that they represented an unconformable series of altered sedi- 

 ments, overlying the Grenville limestones and gneiss and beneath the 

 recognized Huronian; the other was the presence of Eozoon, which was 

 held to represent the first indication of animal life in the Canadian 

 rocks and to pertain to the Laurentian system. He early recognized 

 the fact that the rocks of the Hastings and Grenville series were of the 

 same horizon, and that these rocks extended continuously from the area 

 near Marmora, where they were first studied, across the Ottawa Eiver and 

 up the Gatineau valley as far at least as the mouth of the Desert Kiver, 

 as well as over much of the country adjacent on either side. But ac- 

 cording to the view at that time held as to the composition of the 

 Laurentian, viz., that its u])per member consisted of the auorthosite 

 series, it w;is necessary to include both the Hastings and Grenville scries 

 in the Laurentian also. By some these were regarded as a portion of 

 the lower Laurentian, the anorthosites being regarded as the upper mem- 

 ber, while by olliers they were held to form a middle division; so that, 

 althougli tlie Huronian aspect of the Hastings scrios had been repeated- 

 ly pointed out by different observers, it was practically impossible under 

 the scheme of classification that prevailed at the time to make any other 



