183 JOURNAI. AND PROCEEDINGS 



ing the less promising limestone slabs which afforded quite a 

 number of Ohio and other rare organisms which I have not 

 previously seen recorded as occurring in Canada. 



It was onh' a few daj-s before leaving the camp that I 

 commenced breaking up limestones with no fossil indications, 

 with an appearance (as far as I could recollect) of the ones 

 which proved so unexpectedly rich in former years. The 

 result proved satisfactory. It enabled me to forward to The 

 Dublin Museum a very fine valve of the Ohio Lamellibranch 

 of the late Dr. Jas. Hall, Orthodesuia Curiata. In addition a 

 valve (two I think) turned up of Dr. Billing's Modiolopsis 

 Gesneri. A few more are undetermined. Thej' were 

 extracted from limestones difficult to break up, which 

 probably were washed out of the banks of glacial drift cla}'. 



While asserting the belief that many of our Lov/er 

 Silurian fossils found on the lake shore w'ere derived from 

 glacial clay adjoining, let me hope I may not be misunder- 

 stood as conveying to the Section views I have never enter- 

 tained. Wherever in present or past times, waters of lakes, 

 streams or rivulets encroached on the land, they not only 

 carried awa)' sediment mud, but rolled fragments of lime- 

 stone, sandstone or shale to be deposited at a lower horizon. 

 It is by no means uncommon to find, as already mentioned, 

 Clinton mottled sandstones containing fragments of Lingula 

 (oblonga) Clintoni, evidently brought down from the 

 quarries there by the Grimsby Rivulet in flood. The 

 numerous fragments of Archaean rocks along the shore at 

 Winona, presented similar specimens in the glacial cla5^ 



Note A. — In the foregoing paper the chief object of the 

 writer was to show that many (if not all) the Archsean rocks, 

 found along the shores of Lake Ontario at Winona and 

 Grimsby, were brought to the localities in question by land 

 ice. He extracted a large number of specimens from the 

 Glacial Drift corresponding with others lying loose on the 

 shore. Somewhere to the north of us there must be valuable 

 deposits of red and grey granites. I submit for inspection of 



