76 Scientific Intelligence. 



the Utica terrane and the base of the Silurian, marks another 

 terrane. 



These two faunas are very distinct both in their paleontologi- 

 cal and strati graphical relations. The Lorraine terrane, accord- 

 ing to Dr. Selwyn's classification of formations ( "Index to the 

 Colours and Signs used by the Geological Survey of Canada,") 

 has a definite position, viz : at the summit of the Cambro-Silurian 

 or Ordovician system. The strata of Quebec, either on physical 

 or paleontological grounds, cannot be referred to the Lorraine, 

 nor to the Utica, the Trenton or the Black River formation. 



Sir William Logan referred the Quebec City rocks to the Levis 

 division of the Quebec group. From examinations recently 

 made, the fauna which Mr. Weston, Mr. Giroux, 1'Abbe Laflamme 

 and the writer have been able to obtain from the rocks of that 

 locality, presents some fifty species, including graptolites, brach- 

 iopods, ostracods and trilobites, different from Levis forms and 

 yet capable of being correlated with forms from a portion of the 

 Quebec group of Losran, as described in his Newfoundland , 

 section, as also with Cambro-Silurian strata in the Beccaguimic 

 valley of New Brunswick. 



The strata at Quebec City appear to me to occupy a position in 

 the Ordovician system higher than the Levis formation, being 

 akin to it, but lower than the Trenton, and are probably an up- 

 ward extension of that peculiar series of sedimentary strata in the 

 St. Lawrence valley, which, owing to the conditions of deposition 

 Sir William Logan advisedly classed under the term " Quebec 

 Group." This would make the rocks about equivalent to the 

 Chazy formation of New York. As to the propriety of retaining 

 the term "Hudson River" group, in geological nomenclature, 

 there may be doubt. It would very naturally follow, however, 

 that some such designation as the "Quebec terrane" or "Quebec 

 formation " would be most acceptable for the Quebec City rocks, 

 or those which constitute the citadel and main portion of Quebec 

 City and other synchronous strata. The term " Hudson River " 

 is extensively used throughout North American geological no- 

 menclature to designate the series of strata above the Trenton 

 limestone, much more so than the equivalent term, " Lorraine," 

 defined and very carefully used by Emmons. While neither 

 term is objectionable, and both have been used by various 

 authors for the same horizon, it appears most practical now to 

 retain the term Hudson River, or Hudson Terrane, which has 

 been most extensively used and adopted in North American 

 geology, as this would entail much less confusion, and would 

 thus serve the ends of geological science more effectively. 



The most characteristic species of graptolites peculiar to the 

 Quebec terrane are the following : — (Jcenograptus gracilis Hall, 

 Dicellograptus sextans Hall, D. divaricatus Hall, Dicrano- 

 graptus ramosus Hall, Diplograptus foliaceus Murchison, D. 

 Whitfieldi Hall, D. marcidus Hall, Climacograptus bicomis 



