253 



Such is the series of rocks seen hj me in the vicinity of Quebec. 

 Mr. Logan says, " from the physical structure alone no person would 

 suspect the break that must exist in the neighborhood of Quebec ; and 

 without the evidence of the fossils eve) y one would be authorized to 

 deny it ; " thus throwing on Paleontology all the mistakes made and all 

 the difficulties accumulated in his Quebec Group. I ask permission to 

 say that the Stratigraphical and Lithological differences between the 

 Silurian and Taconic rocks of the vicinity of Quebec are to me at 

 least as great and as plain as the Paleontological ones ; and that I find 

 no facts whatever which show any conflict between Paleontology and 

 Stratigraphy. 



It is doubtful if all the shales between the chasm of Montmorency 

 Falls and the waters of the St. Lawrence are of the Utica Slate age ; 

 the Grapioliias bicornis and G. pristis are found in the Uach shales 

 near their contact with the Trenton Limestone, but as yet no fossils 

 have been found in the gray shales. In the ravine east of the Falls, 

 there is probably a fault between the black and gray Shales ; the 

 dipping of the Trenton Limestone, the black Shales and gray Shales, 

 disagrees, and varies from fifteen to eighty degrees, in a space of less 

 than 150 feet. I am inclined to consider the gray Shales as the upper 

 part of the Calciferous Sandstone group, but it will require further 

 investigations in the field to determine the true stratigraphical struc- 

 ture of Montmorency Falls. 



The Corresponding Secretary read letters from Dr. Chris- 

 tian Liitken, of the University of Copenhagen, and Dr. B. F. 

 Shumard, of St. Louis, Mo., acknowledging their election as 

 Corresponding Members of the Society; also, a letter from the 

 Entomological Society of Philadelphia, acknowledging the re- 

 ception of the Society's Pioceediugs, Yol. viii., pp. 161 — 192. 



On motion of Prof. Rogers, G. B. Emerson, Esq., and Rev. 

 R. C. Waterston, were added to the Building Committee. 



Mr. William C. Cleveland, of Cambridge, was chosen a 

 Resident Member. 



Nommher 20, 1861. 

 The President in the chair. 

 The following communications were presented : — 

 Note ox Cleaning Diatomaceje. By Arthur M. Edwards, 

 New York. 

 Not having found any of the published methods for cleaning sub- 

 peat deposits or guanos, so as to develop the Diatomaceae contained in 



