PALEOZOIC TIME — CAEBONIC. 659 



In the Wasatch, the Carboniferous beds are about 13,000' thick, the Upper Coal- 

 measure limestone 2000' thick ; below this is the Weber quartzyte, 6000'; and then 5000' 

 of the Wasatch limestone, the lower part of which contains Subcarbonif erous fossils. The 

 Carboniferous formation in the Eureka basin, Nevada, has a total thickness not far from 

 10,000', of which the Weber conglomerate comprises 2000', and a quartzyte at the base, 

 3000'. The upper member is only 500' thick, but has a thickness of 2000' to the north- 

 west. (Hague.) 



In California, Carboniferous beds, consisting partly of limestone, occur in the Sierra 

 Nevada along a broad belt west of, and nearly parallel to, its axis. They extend inter- 

 ruptedly, says Whitney (1866), from Shasta County, near Pitt River (40° 45' N. where 

 limestone of the p)eriod was first identified by Trask in 1855) through Plumas County, 

 southwestward, to the Tahichipi valley, more than 500 miles. The limestone occurs at 

 intervals interstratified with the argilly te, mica schist, and siliceous slates of the auriferous 

 series, and disappears at times, as Whitney states, by graduating into calcareous sand- 

 stones and the siliceous slate. The fossils obtained by Trask near Bass Ranch, comprising 

 species of Fusulina (Fig. 1069), a Lithostrotion hardly distinguishable from L. mammillare, 

 and other kinds, were referred by Meek, with much expressed doubt, to the Subcarbo- 

 nif erous ; and Gabb suggested the same conclusion for the fossils of the limestone at 

 Pence's Ranch, 80 miles to the southeastward. H. W. Turner reports Fusulina from 

 Kite's Cove, Mariposa County, and, from other parts of the same interrupted limestone 

 belt, in Calaveras and Amador counties, and at different points in Plumas County. It is 

 probable that the rocks are partly at least of the Carboniferous period. 



Carboniferous rocks occur also in the Klamath Mountains and Coast Range, according 

 to Fairbanks and Diller. But they have not yet been identified in Oregon and Washington. 

 They exist in British Columbia, in some parts of the Coast region, and are extensively 

 distributed over the interior plateau, extending northward as far at least as the Peace 

 River region, in latitude 55°-56° N. 



In the Arctic regions, Carboniferous beds are reported from Melville Island, at Cape 

 Dundas, Bridgeport Inlet and Skene Bay ; Baring Island at Cape Hamilton ; Byam Martin 

 Island ; and on Bathurst at Schomberg Point and Graham jMoore Bay. The line of outcrops 

 of the beds runs E.N.E. They are accompanied by clay ironstone in nodules, as is usual 

 in coal regions (Haughton). For notes on the Carboniferous areas of the Arctic regions, 

 see, further, G. M. Dawson, Bep. Geol. Canada, for 1886. 



In Mexico, Carboniferous limestone, representing the Carboniferous period, or the 

 Carboniferous and Permian periods, has been observed in some of the ridges and mountains 

 of Coahuila and Nuevo Leon (Frazer and Hall), and also on the borders of Mexico and 

 Guatemala ; also, in Nicaragua, with overlying Permian and underlying Silurian and 

 Devonian (Crawford, 1890). 



In South America, the Carboniferous beds have great extent in Brazil, in the 

 Amazon valley, — as great as the North American Carboniferous, — but they afford no 

 coal (Derby, Am. Jour. Sc, xvii., 1879). 



The following probable correlations are based by Lesquereux on the distribution of the 

 species of coal-plants : — 



Coal A, which exists within the Pottsville conglomerate, or Millstone grit, at the basis 

 of the Coal-measures, or its equivalent plant-bearing beds : at Shamokin, Lehigh Summit, 

 lower bed at Trevorton, Broad Top, in Pennsylvania ; at Massillon, Ohio ; at Union Mines, 

 in Crittenden County, Kentucky. 



Coal B, Archbald, Pa. ; Spring Creek, Ind. ; Union, Greenup, and Carter counties, 

 Ky. ; Murphysboro, Mazon Creek, Morris, 111., in shale over coal. 



Coal B or C, Carbondale, Pa. ; Cannelton, Pa. ; Clinton, Mo. 



Coal C, Archbald, Shamokin, Pittston, at Boston mine, etc. ; Eugene, Vermilion 

 County, Ind. 



