371 



Distribution oi the Species. 



The distribution of the speciea in the foregoing catalogue, may be dis- 

 cussed in the following order. 



Potsdam Gkoup. 



In this group, consisting of Divisions A, B, and C, we have nineteen 

 species, none of which are found in the Potsdam sandstone in Canada. 

 But in that part of the group, which is usually known, in the State of 

 Vermont, under the designations of the Red Sand Rock, and the Georgia 

 slates, the following occur : — ScolitJius linearis, Palceophycus incipiens, 

 Obolus Labradoricus, Obolella (^Kutorgind) cingulata, Olenellus Thomp- 

 soni, 0. Vermontana, Conocephalites Adamsi and 0, Teucer. As these 

 are the most abundant species in the formation, both in Vermont and 

 Newfoundland, there can be little doubt, but that the rocks in which they 

 occur, in these two widely separated localities, are of the same age. None 

 of these species have been found in the Potsdam sandstone of Wisconsin, and 

 other parts of the Western States as described by Owen, Hall, Shumard, and 

 Meek. We have, therefore, no palseontological evidence that the Potsdam 

 of the West is precisely of the same age as that of Newfoundland and 

 Vermont. The general affinities and aspect of the fossils and the physical 

 relations of the rocks, however, prove that there can be no great difference. 

 In the next overlying strata Division D, Lingula acuminata was found 

 at Bay St. Barbes. I have compared the specimens from this locality 

 with those that occur so abundantly in the upper part of the Potsdam, in 

 the Township of Beverley in Canada West, and beUeve them to be per- 

 fectly identical. 



Calciperous Formation. 



The Calciferous formation is represented in Newfoundland, by all the 

 Divisions from D to H inclusive. In this series of strata, there are sixty- 

 three species, of which the following fourteen are found in Canada and 

 New York ; Stenopora fibrosa, Stromatopora rugosa ?, Lingula acumi- 

 nata, Eiichasma Blumenbachia, Pleurotomaria Calphurnia, P. calei- 

 fera, P. Laurentina, Murchisonia Anna, Ucculiomphalus Atlanticus, 

 Orthoceras LamarcM, Piloceras Canadensis, Bathyurus Cordai, Asaphus 

 canalis, and Leper ditia turgida, — excepting S. fibrosa and B. Cordai, all of 

 these occur in the true Calciferous in Canada. B. Cordai abounds in the 

 same formation in New York. ^S*. rugosa is doubtfully determined, and 

 is probably distinct from the Black River species of that name. The beds 

 in which L. acuminata occurs in Canada, are placed in the top of the 

 Potsdam ; but as Pleurotmaria Canadensis, and an orthoceratite, are asso- 



