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PALEOZOIC TIME. 



age, showing that it is older. The rocks on Keweenaw Point include 8.000 to 1G,000 

 feet of sandstone and conglomerate (Whitney), along with intersecting trap rocks and 

 some intercalated scoria-conglomerate. East of this point, there are in the same sand- 

 stone formation the Pictured Rocks of the coast — fine sandstones blotched or mottled 

 with red or light gray. Westward, the sandstone extends to the west end of the lake, 

 and then northward and eastward to Thunder Bay and Neepigon Bay. The rocks of 

 Isle Royale and Michipicoten Island are of the same age. The formation is remark- 

 able for its copper mines. In Canada, the Calciferous sandrock has a thickness of 50 

 to 300 feet. 



b. Appalachian Region. — The Auroral series of Rogers, in Pennsylvania, corre- 

 sponds, according to him, to the Calciferous, Chazy, and Black River beds, and con- 

 sists mainly of magnesian limestone; it is from 2,500 to 5,000 or 6,000 feet in thick- 

 ness. 



In eastern Tennessee, near Knoxville, the Calciferous includes the " Knox sand- 

 stone " of Safford, the lower member of the Knox Group (F. H. Bradley). 



2. Quebec epoch — Near Quebec, the beds are largely developed on the island of 

 Orleans and in the district around Point Levis. From the Levis beds, Logan separates 

 the upper part, occurring more to the southward and southeastward, which is destitute 

 of fossils and consists mainly of copper-bearing metamorphic schists, and designates 

 it the Lauzon division. He also adds to the series the " Sillery Sandstone " (so called 

 from a place near Quebec) as an upper member, the actual connection of which with the 

 system is not clear. 



In the vicinity of Quebec, the thickness of the Levis beds is said to be 5,000 feet; 

 4,000 feet of the whole are gray and green shales, 155 feet intercalated beds of lime- 

 stone (half of it limestone-conglomerate), and 700 feet gray sandstones partly shaly. 

 The shales are either calcareo-magnesian, argillaceous or arenaceous. Many of the 

 beds abound in fossils. Logan supposed the Quebec slates to extend south along the 

 Hudson River; but the discovery of fossils of the Trenton period in Dutchess County, 

 at Poughkeepsie, aud elsewhere, has proved this to be an error. 



In northwestern Newfoundland, the thickness of the "Quebec series" is 6,600 feet, — 

 the lower 3,200 feet mostly limestones, and the rest sandstones and shales, with some 

 conglomerate limestone. The upper 2,000 feet are separated by Logan and Billings as 

 " Sillery; " the next 1,400, of sandstones and shales and some limestones, as "Levis, " 

 and the lower beds, 1,839 feet thick, of limestones, as Calciferous. Between these 

 Calciferous beds and those referred on paleontological evidence to the Levis, there are 

 2,061 feet of fossiliferous limestone, which have no equivalents in Canada, and are called 

 Upper Calciferous, in distinction from the New York beds which are hence made 

 Lower Calciferous. "It thus appears that the 'Levis' formation not only lies above 

 the Calciferous, but more than 2,000 feet above it." (Billings.) 



The Quebec group in Tennessee, about Knoxville, includes the shale and dolomite of 

 the " Knox group " of Safford (F. H. Bradley) : the base of the dolomite abounds in trilo- 

 bites characteristic of the group. In Idaho, Bradley found the group on the east side 

 of Malade valley, six miles south of Malade city, 2,000 feet thick, mostly of limestone, 

 underlaid and overlaid by quartzyte; and in the Teton range, at the base of the lime- 

 stones over the granites of the range (Am. Jour. Sci., III. iv., vi.), and separated 

 from the latter by only a few feet of quartzyte referred to the Potsdam epoch. 



3. Chazy epoch. — (a.) Interior Continental basin. — The Chazy limestone out- 

 crops at different places in northern New York, in the vicinity of the Archaean 

 (though not along its more southern border); also in Canada, around the Trenton 

 limestone of the Ottawa basin. The thickness in some parts of New York is 100 to 

 150 feet. Occasionally, it graduates into the next rock below, the Calciferous sandrock, 

 so that the two are separated with difficulty. 



The reference of part of the limestone formation of the Green Mountain region to the 

 Calciferous and Chazy epochs, extending through Vermont, Western Massachusetts and 

 Connecticut, and the eastern border of New York, is based on the discovery of fossils in 

 it in Vermont by A. Wing, among them a Crinoidal plate of PalcBocystites tenuira- 



