248 THE CANADIAN NATURALIST. [Yol vi. 



Yl.—Rlver St. Lawrence above Quebec, and Ottawa Valley. 



Quebec and its Vicinity. — The deposits at Beauport, near 

 Quebec, were described by Sir C. Lyell in the Geological Trans- 

 actions for 1839; and a list of their fossils was given, and was 

 compared with those of Montreal in my paper of 1859. As 

 exposed at the Beauport Mills, the Post-pliocene beds consist of 

 a thick bed of Boulder-clay, on which rests a thin layer of sand 

 with Rhynconella j^sittacea and other deep-water shells. Over 

 this is a thick bed of stratified sand and gravel filled with Saxi- 

 cava rugosa and TelUna . In a brook near this place, and also 

 in the rising ground behind Point Levi, the deep-water bed 

 attains to greater thickness, but does not assume the aspect of a 

 true Leda clay. Above Quebec, however, the clays assume more 

 importance; and between that place and Montreal are spread 

 over all the low country, often attaining a great thickness, and not 

 unfrequently capped with the Saxicava sand. At Cap a la 

 Pioche the officers of the Geological Survey have found a bed of 

 stratified sand under the Leda clay. The Beauport deposit is 

 evidently somewhat exceptional in its want of Leda clay, and this 

 I suppose may have been owing to the powerful currents of water 

 which have swept around Cape Diamond at the time of the ele- 

 vation of the land out of the Post-pliocene sea. The layer of 

 sand at the surface of the Boulder-clay is evidently here the 

 representative of the Leda clay, and afibrds its characteristic 

 fossils, while the stones projecting above the Boulder-clay are 

 crusted with Bryozoa and Acorn-shells. At St. Nicholas, there 

 is a sandy Boulder-clay, not unlike that of Riviere-du-Loup, 

 which has afi'orded some very interesting fossils. It is stated 

 in the Report of the Survey to be one hundred and eighty feet 

 above the sea. 



' Montreal. — la the neighbourhood of Montreal very interesting 

 exposures of the Post-pliocene beds occur, and with the terraces 

 on the Mountain have been described in my papers of 1857 and 

 1859. I may here merely condense the leading facts, adding 

 those more recently obtained. 



