PARALLELISM OF THE QUEBEC GROUP. 27 



them either to the " upper part of the Calciferous formation" or 

 to " beds holding fossils approaching in aspect to those of the 

 Chazy or Black River formations^ 



The upper limits of the Quebec group, having been determined 

 as above, it remains next to show how far it extends downwards. 

 On this point I have only to say, that in Newfoundland, Mr. Rich- 

 ardson has discovered a series of rocks, which I have not the least 

 hesitation whatever, in pronouncing to be positively identical in 

 age with both the Loint Levis and Phillipsburgh limestones. He 

 has also ascertained, by a good coast section, that they clearly 

 overlie all that part of the Calciferous which holds the remark- 

 able- and characteristic cephalopods of Mr. Salter's new genus 

 Piloceras. These beds in their turn overlie conformably the sand- 

 stones holding Lingula acuminata, which characterizes the upper 

 strata of the Potsdam, in Canada West, New York, and Wiscon- 

 sin. We thus have two horizons well determined, between which 

 the Quebec group (or at least that portion of it to which the 

 Point Levis and Phillipsburgh limestones belong) must be situ- 

 ated. The lower horizon is about the middle of the Calciferous, 

 and the upper near the base of the Black River limestone.* 



It follows from what has been above stated, that the Chazy 

 limestone occupies a position between the same two horizons 

 which limit the Quebec group above and below. Are these two 

 formations i.e., the Chazy and the Quebec group, of the same 

 age ? On this point all that can be said is that the Quebec group 

 holds about 300 species of fossils (including the graptolites), and 

 I cannot identify a dozen of them with true Chazy species. My 

 own view is, that in a portion of the Quebec group, we have a set 

 of strata representing those which are absent in Canada, west 

 of the line where the break occurs between the Calciferous 

 and Chazy formations. The remainder may possibly be of 

 the age of the Chazy, the difference in the species being due to 

 geographical distribution. I only offer this however as a possible 

 solution of one of the difficulties that have been met with, in en- 

 deavouring to arrive at the truth, in this complicated question. 



* It is possible that the lower part of the true Calciferous may be 

 represented by some of the slates in the south-eastern region in which 

 no fossils have yet been found. 



