to Quebec one side from - plain, There is the Ordovician plain. and subsequent ^ no reason why the Ordovician plains should not have spread far at wide over the St. Lawr- rence Valley. This became of its peculiar low altitude. In many places along the St. Lawrence the plain is flat and rises gently north. It is a soft red sand = "St. Lawrence" glacial clays, Wherever the higher ground appears it is with Trenton or glacial breccias. West of Louisville there is a flat^2 ridge justable more than 100 feet high.^1 To the south of this is the same flat plain of glacial clay. The ridge may have been a former bounding edge of the St. Lawrence. Near Portneuf or 138 miles E. N marked the history of change and the country became more hilly and higher. The river too is in a deep canyon. The broad Ordovician plain is about gone and from here east the top- gently becomes more and more that very hilly. Later it is probable that the Ordovician plain thin farther Quebec, to the north. I saw no more Trenton hills exposures much farther east than Three Rivers, or Quebec. Very cool days in June shading all way.