; 
356 TRANSACTIONS OF THE CANADIAN INSTITUTE. (VoL. VIII. 
stratigraphical horizon. It contains pebbles of every older formation 
represented in the region besides some of rocks which are not common 
there. The largest and most prominent pebbles are granite, but there 
are also pebbles of greenstones, quartz-diorite porphyry, green schist, 
carbonate schist and jasper, cemented together by a matrix of fine grained 
green material. A thin section of one pebble contained large phenocrysts 
Lower Huronian Conglomerate, Lake Corrigan 
of plagioclase showing the polysynthetic twinning, crystals of hornblende, 
some quartz and fine grained material, the whole being considerably weath- 
ered. On the line along the east side of location HF27 and just south of 
Whitefish Lake there is some conglomerate containing pebbles of the 
carbonate schist. These are fairly well rounded, but have been somewhat 
deformed by shearing. They lie in a matrix containing a good deal of 
iron carbonate and as the outcrop is beside an exposure of the carbonate 
schist it appears that the conglomerate has been derived directly from 
this rock. 
The conglomerate north of Wendigokan contains less jasper and 
