252 THE CANADIAN NATURALIST. [Vol. Vl. 



The whole of these deposits except the Leda clay, are very 

 irregularly bedded, and are apparently of a littoral character. 

 They seem to shew the action of ice in shallow water before the 

 deposition of the Leda clay. The only way of avoiding this 

 conclusion would be to suppose that the underljdng beds are 

 really of the age of the Saxicava sand, and that the Leda clay 

 has been placed above them by slipping fram a higher terrace ; 

 but I failed to see crood evidence of this. A little farther west 

 at the gravel pits dug in the terrace for railway ballast, a deep 

 section is exposed showing at the top Saxicava sand, and below 

 this a very thick bed of sandy clay with stones and boulders, con- 

 stituting apparently a somewhat arenaceous and partially stratified 

 equivalent of the Boulder-clay. A little above this place, at the 

 Brick-works, the Saxicava sand is seen to rest on a highly fossil- 

 iferous Leda clay, which probably here intervenes between the 

 two beds seen in contact nearer the edge of the terrace. 



Ottawa River. — The Leda clay and Saxicava sand arc well 

 exposed on the banks of the Ottawa; and Green's Creek, a little 

 below Ottawa City, has become celebrated for the occurrence of 

 hard calcareous nodules in the clay, containing not only the 

 ordinary shells of this deposit, but also well-preserved skeletons of 

 the Capelin (^Mallotus) of the Lump-sucker (Cycloiiterus) and of 

 a species of stickleback (^Gasterosteus). Some of these nodules 

 also contain leaves of land plants and fragments of wood, and a 

 fresh-water shell of the genus Lymnea has also been found. 

 At Packenham Mills west of the Ottawa, the late Sheriff Dickson 

 found several species of laud and fresh-water shells associated 

 with Tellina Groenlandica and apparently in the Saxicava sand. 

 These facts evidence the vicinity of the Laurentian shore, and 

 indicate a climate only a little more rigorous than that of Central 

 Canada at present. They were noticed in some detail in my 

 paper of 1866 in The Canadian N^aturalist.. 



The marine deposits on the St. Lawrence are limited, as already 

 stated, to the country east of Kingston ; and the clays of the 

 basin of the great lakes to the south-westward have, as yet, 

 afi'orded no marine fossils. I have, however, just learned from 

 Prof. Bell, uf the Geological Survey, a discovery made by him 

 in the past summer and which is of very great interest, namely 

 that two hundred miles north of Lake Superior the marine 

 deposits reappear. The details of this important discovery will 

 be given in a forthcoming Report of the Geological Survey^ 



