370 Revieivs — Prof. C. Lapworth's Canadian Graptolifes. 



The most important and interesting point in connexion with this 

 Marsouin Eiver zone is its identity with that of the Norman's Kill 

 shales in the Hudson Eiver valley, near Albany, described by Prof. 

 James Hall in the " Palseontology of New York.''^ 



The New York geologists have always held that the Norman's 

 Kill beds are of the age of the Hudson Eiver (Lorraine Shales), or 

 of that of the Utica Slate ; but Prof. Lapworth observes, " not a 

 shadow of palasontological evidence has yet been adduced to show- 

 that these Norman's Kill or Marsouin Eocks are newer than the 

 Trenton." On the whole he regards the Marsouin zone provisionally 

 as coming between the Chazy (holding Mudurea Logani and OpM- 

 leta compacfa) and the Trenton Limestone in America, and therefore 

 answering roughly to the Ccenograptus gracilis zone in Britain, " in 

 age as well as in fossils." 



As a result of his analysis of the three Graptolitic zones above 

 detailed, Prof. Lapworth finds that there are two grand faunas 

 represented, viz. : — (A) The so-called Quebec fauna of the Calcifer- 

 ous-Chazy formations of Cape Breton, Cape Eosier, Point Levis 

 and Ste Anne, which answers to the fauna of the British Upper 

 Tremadoc and Arenig rocks and their European equivalents ; and 

 (B) the Griffin Cove, Marsouin Eiver, and Norman's Kill fauna, 

 which answers to the fauna of the middle zones of the European 

 Ordovician or Cambro-Silurian rocks. 



In each, of these grand faunas are found two subfaunas, those of 

 the lower faunas being the more distinctly separable : — 



A. Quebec ok Calciferous-Chazt Fauna. — Subfauna L — Cape 



hosier and Barrasois Biver Zone, of Calciferous age =: Tremadoc 

 Eocks of Great Britain and Ceratopyge and Dictyonema Beds of 

 Norway. 

 Subfauna IL — Ste Anne Biver Zone, of Point Levis age = typical 

 Arenig of Great Britain ; PJiyllograptus Beds of Scandinavia, etc. 



B. Tkentonian, Maksouin Eiver, ok Nokman's Kill Fauna. — 



Subfauna A. — The Ccenograptus Zone of Griffin Cove and the 

 Marsouin Biver, answering to the Middle Llandeilo Beds of 

 Great Britain, to the Glenkiln Beds of Scotland, etc. 

 Subfauna £. — The Cove Fields and Orleans subfauna; apparently 

 destitute of Ccenograptus gracilis, and answering to the highest 

 Llandeilo or lowest Caradoc Beds of England. 

 The last of these subfaunas shows evidence of a transition into the 

 Utica-Lorraine Graptolitic fauna of the Mohawk Valley, New York, 

 and of Lake St. John, Canada." 



The author next presents a " Possible Ascending Succession of 

 Strata, on the South Side of the St. Lawrence, from Cape Gaspe to 

 Tartigo Eiver," which includes 



Pre-Cambeian. 

 {A). Metamorphic Eocks of the Shickshock Ranges [in the Gaspe Peninsula], 



Cambrian. 

 (B). Camhrian Formations. 



Ordovician. 

 (C). OrdoTician or Cambro-Silurian Formations. 



1 Vol. i. 1847. 



