AMERICAN GEOLOGY DECAD*E OF 1860-1869. 517 



the Jura-Trias age of these rocks, and the extracts from the published 

 reports seem to bear him out. 



The second volume of the paleontological reports, as published in 

 1869, comprised 299 pages, with 36 full -page plates, and was given up 

 wholly to descriptions of Tertiary and Cretaceous fossils by Gabb. 

 In his introductory note Whitney reiterated his statement above quoted 

 reerardiner the a^e of the gold-bearing rocks and the absence of rocks 

 older than Carboniferous, not merely in the State, but west of the 

 one hundred and sixteenth meridian. 



As previously noted (p. 385), Logan, during his period of service 



as provincial geologist, submitted sixteen reports dealing mainly with 



stratigraphic and economic subjects. In 1863 he brought forward a 



long promised volume — The Geology of Canada — a 



cSa! ?863 gy ° f large octavo, of 983 pages, accompanied by an atlas 



giving a colored geological map and sections. 



Logan was assisted during the early part of his work by Alexander 

 Murray and James Richardson, geologists; E. Billings, paleontolo- 

 gist, and T. Sterry Hunt, chemist. Later Robert Bell, now (1904) 

 acting director, and others of less prominence, were added to the 

 force. A portion of the paleontology was assigned to James Hall, 

 and the nomenclature adopted was essentially that of the New York 

 survey. 



The map accompanying the volume was beautifully executed in 

 colors, and comprised all of the provinces southeast of the St. Law- 

 rence as well as a narrow belt composed mainl} T of Laurentian, 

 extending from Labrador southwesterly to the Great Lakes, and 

 thence north westerly to the ninety-sixth meridian. It included a 

 considerable portion of the United States, data for which were sup- 

 plied by Hall and other American geologists. 



Overlying the graptolitic shales of the Utica and Hudson River 

 formations in the vicinity of Quebec, Logan found a conformable 

 series of sandstones, shales, and conglomerate limestones, which he 

 considered, in spite of their position, as older than the Hudson River 

 group formation and to which he applied, from their geographical 

 position, the name of the Quebec group. This was again subdivided 

 into an underlying green sandstone series called the Sillery formation, 

 and an overlying Levis formation. These were supposed by both 

 Logan and Billings to be mainly contemporaneous with the Calcifer- 

 ous and Chazy groups of the New York geologists, but more recent 

 investigations by Selwyn and Ellis have shown that while the Levis 

 beds are Calciferous in the lower parts, the Sillery is probably all 

 Cambrian (Dana), the Quebec, as a whole, being a northern continua- 

 tion of the Taconic series. By a singular error, to which Marcou 

 was prompt to call attention, this Quebec group on the map referred 



