480 G. King—Qeology of the 40ih Parallel 



Zaphrentia eccentrica Meek. Productus Flemingi, va7 



White f " sp.? resembles S. imbrex 



semireticulatus Mart Hall 



elegans N. & P.? Athyris subquadrata Rail. 



From the evidence in the Oquirrh Eange it would seem that 

 the Sub-carhoniferous and Waverly together cannot be less than 

 1,000 feet thick. Through the 'remainder of the Wahsatch 

 limestone, up to its very summit — a thickness of at least 4,0U0 

 feet above the Sub-carboniferous — are found at intervals beds 

 carrying distinct Coal-measure forms. This immense body of 

 limestone therefore, represents 4,000 to 4,500 feet of Coal- 

 measures, 1,000 to 1,200 feet of Sub-carboniferous and Waverly, 

 and 1,000 to 1,400 feet of Devonian, all these figures varying 

 slightly according to the general expansion or contraction of the 

 Wahsatch limestone as a whole in different localities. 



Next in the series above the Wahsatch limestones occurs a 

 very^ remarkable bed of siliceous material, which we have named 

 the Weber quartzite from a typical occurrence in the Weber 

 canon of the Wahsatch Eange. Here, conformably overlying 

 the limestone, is a body of quartzite about 6,000 feet in thick- 

 ness, having a few red sandstones at the base, and occasional 

 limited fine beds of shale interspersed at three or four different 

 horizons through the body, and varied to a considerable extent 

 by thin sheets of conglomerate and rounded quartz pebbles. It 

 has never in this locality yielded any fossils ; but its reference 

 to the middle of the Coal-measures is rendered absolutely cer- 

 tain by the collection of great numbers of different Coal-measure 

 fossils" from the Wahsatch limestone below and from an overly- 

 ing body of limestone to be described later. In the canon of 

 the Weber, this Weber quartzite has a minimum thickness. In 

 the Oquirrh it has been estimated to be 9,000 or 10,000 feet ; 

 and unless we have made some errors in the assignments of 

 horizons in western Nevada, it there reaches an even larger 

 figure. To this member of the series we have referred the 

 great body of sandstones with intercalated shales and conglom- 

 erates which form the body of the Uinta Eange, and there dis- 

 play a thickness of certainly over 10,000 feet, and accordmg to 

 Major Powell, a much greater thickness. The evidence on 

 which this is referred will be detailed in the forthcommg geo- 

 logical report of this exploration. The Weber quartzite is ex- 

 ceedingly variable in its thickness and mechanical condition. 

 For the most part it represents a true quartzite, but here and 

 there at various localities it is less altered and is merely a s&nes 

 of coarse granular sandstones. At several places in the Wah- 

 satch this body of quartzite is exposed between the two Coal- 



