LEVIS AND SILLERY FOSSILS. 493 



These fossils were all derived from the shales and evenly bedded limestones 

 of Levis age. This number and list can no doubt be swelled considerably 

 after careful collecting and determination. There are many species both of 

 Cambrian and Cambro-Silurian (Ordovician) age included in the pebbles of 

 the conglomerates of the Levis terrane. These should be carefully collected 

 and noted. Fossils from the paste of the conglomerate, if any, should be 

 carefully kept separate, and interesting results will no doubt be forth- 

 coming. 



The Sillery. — Underlying the Levis and faulted together at many points 

 we find the Sillery, red, green and black shales associated with sandstones 

 and conglomerates. The leading paleontological characters of this series so 

 far is the presence of Obolella (Linnarssonia) pretlosa, Billings, in great 

 abundance wherever that terrane is met with. At the Chaudiere River 

 railway bridge this shell occurs in great abundance, associated with other 

 forms of Obolella and two species oi Lingida ; also with a Protospongia, akin 

 to P. tetranema, Dawson. The presence of these spicules of sponges, referred 

 to the genus Protospongia by the writer in 1883 along with Obolella, point 

 clearly to the antiquity and earlier age of the Sillery than that to which it 

 was for a long time assigned. A number of obscure compound graptolites 

 and a species of Phyllograptus also occur at the Chaudiere river exposures, 

 indicating the probably transitional character of these passage beds between 

 the Cambrian and Cambro-Silurian (Ordovician) epochs. 



Conclusion. 



Having thus briefly described the various terranes as they are seen along 

 the line of section north and south, it will be observed on resuming the ques- 

 tion of the probable age of the Quebec city massif that, when these are com- 

 pared with the Levis terrane, their physical character, the presence of the 

 conglomerate bands, the similarity of strata in sedimentation and in their 

 lithological characters, together with the general field aspects give them, 

 owing to their intimate relations as having been subjected to similar press- 

 ures and foldings, the appearance of being a part and parcel of that greater 

 series of sedimentary strata to which Sir William Logan advisedly gave the 

 name " Quebec group." It would also appear that the Quebec terrane, 

 while distinct from the Levis terrane paleontologically, still exhibits numer- 

 ous points in contact and would form an upward extension of that series 

 at the base of which we find the Sillery. This would, I hold, materially 

 assist in demonstrating the proper interpretation of the term " Quebec group " 

 as Sir William Logan and Mr. Billings knew it, as regards the fossiliferous 

 portion of that interesting series of sedimentary strata. 



LXXII-BuLL. Geol. Soc. Am., Vol. 2, 1890. : 



