CANADA. 347 



square, of labradorite-rock, shewing considerable varieties in character, and 

 clearly stratified." [l. c, pp. 305-307.) 



Mr. Richardson's work failed to prove his conclusions, as the rocks 

 were not shown to be sedimentary. 



In 1868 Mr. J. Marcou wrote regarding the Laurentian and Huronian 

 formations : — 



" The Laurentian system is composed of the Lower Taconic, to which are 

 added all the unstratified crystalline rocks forming the centre of the Laur^ntine 

 Mountains, such as granite, syenite, diorite and porphyry, mixing together 

 strata and eruptive rocks, an attempt which was unexpected from a strati- 

 graphical geologist. His Huronian system is formed of a mixture of the St. 

 Albans group of the Upper Taconic, with the Triassic rocks of Lake Superior, 

 the trap native-copper bearing rocks of Point Keeweenaw, and the dioritic dyke 

 containing the copper pyrites of Bruce mine on Lake Huron." (Proc. Lost. 

 Soc. Nat. Hist., 1861, VIII. 246, 247.) 



In the Report of Progress for 1870-71, Mr. Robert Bell points out a 

 case of an apparently conformable junction of the Huronian and Lau- 

 rentian rocks. He remarks : — 



" From the mouth to the sixteenth portage .... the river [White River] 

 runs entirely upon greyish and reddish gneiss, mostly of a massive granitic 

 character [Laurentian], striking "W. S. W., and dipping northward at angles 

 varying from 30° to 80°. It is occasionally interstratified with bands of dark 

 hornblendic schist and very light gi'ey gneiss. Fine dark green hornblendic 

 schists [Huronian], having the same strike, occur between the sixteenth port- 

 age and the outlet Similar schists [Huronian], with bands of gneiss, 



appear to rest conformably upon the massive gneisses at a short distance north 

 of the river, all the way from Natamasagami Lake to the mouth (28 miles)." 

 (I. c, p. 345.) 



Of another locality Mr. Bell, in the Report for 1871-72, states : — 

 " Towards the end of the above twenty miles, bands of gneiss become inter- 

 stratified with the schists, and just at Martin's Falls the latter have become 

 entirely replaced by red and grey gneiss, apparently shewing a conformable 

 passage from the Huronian into the Laurentian rocks. AVhat appeared to be a 

 similar blending of these formations was noticed last year in the neighbor- 

 hood of White Lake." (I. c, p. 110.) 



In the Report of Progress for 1872-73, Mr. Bell again states, regard- 

 ing the rocks northwest of Lake Superior : — 



" As mentioned in the present and in my prcAuous reports on this region, the 

 Huronian rocks appear to succeed the Laurentian conformably, the distinction 

 between the two being chiefly of a lithological character. As nearly as the 



