424 THE CANADIAN NATURALIST. [DeC. 



for a similar reason, the Saxicava sand, formed in shallow waters. 

 On the south bank of the Ottawa River, from this city to Hawkes- 

 bury, the lower clay formation of Dr. Dawson is to be seen in 

 banks from twenty to forty feet high. ^' The overlying sand gene- 

 rally approaches the river and conceals the clay except along the 

 streams." Wherever these clay formations exist along the river 

 the shells Saxicava rugosa and Tellina Groenlandica are to be 

 found, and in a bed of clay at Green's Creek nodular masses exist 

 in considerable abundance. The most common fossil embedded in 

 these, is the Mallotus villosiis or capeling of the Lower St. Law- 

 rence. This capeling is also found in nodules, in clay, on the 

 Chaudiere Lake, 183 feet ; on the Madawaska at 206 feet ; and at 

 Fort Coulonge Lake, at 365 feet above the sea. This formation 

 contains also various other fossils. On the north side of the 

 Ottawa, from Hull to Isle Jesus, this clay formation covers a con- 

 siderable breadth between the Laurentian Hills and the river. It 

 can also be traced in considerable abundance along the banks of 

 the Gatineau and river Rouge. In the former locality it is well 

 known to the lumberers, who in wet weather describe it as the 

 sticking clay of the Gatineau. A well-deSned hill of clay exists 

 on the front and to the left of the General Protestant Hospital, 

 facing the Rideau River, and to the rear an extensive mound of 

 sand, both of which are drift formations. The boulder formation 

 or glacial drift, both in the British Isles and North America, is 

 referred by Lyell to the age of the newer pliocene, of which it 

 marks its close ; while the stratified deposits which overlie it, con- 

 sisting partly of boulder formation re-arranged by water, are 

 placed among post-tertiary strata. The records of the drift or 

 boulder period extend over North America, north of parallel 40°, 

 as well as over all the northern countries of Europe, and the 

 various boulders have been moved from the north towards the 

 south. Throughout the regions occupied by the drift, the rocks 

 in place are more or less polished, striated, or grooved. These 

 marks are observed on the consolidated formations that appear at 

 the surface, and constitute a very essential part of the records of 

 this period. 



Rock Basins or Pot-holes. — These are everywhere common 

 along rapid brooks and rivers. They are most frequently seen on 

 elevated ground, and present all the appearances of those formed 

 at water-falls by the gyration of the pebbles. Professor Emmons 

 gives an example of one, as seen at Antwerp, St. Lawrence County, 



