376 INDEX TO THE STEATIGEAPHY OF NOKTH AMERICA. 



most decisive proof of the Upper Carboniferous age of these strata is their position so far above 

 the Baird shales, which have been shown in this paper to be equivalent to the Lower Carbon- 

 iferous of the Eureka district, Nevada, which is known to occur 3,000 feet above the base of 

 the formation. 



The McCloud limestone is probably equivalent to the limestone of the Caribou formation 

 of Plumas County. But J. S. DiUer thinks that they belong to a lower horizon than that 

 assigned them by the writer. The Robinson beds of the TaylorviUe section are probably 

 higher up in the section, but nevertheless the McCloud limestone is, in part at least, equivalent 

 to the Coal Measures. 



Collections obtained by Diller were subsequently studied by Girty, who finds 

 "little of material importance" to add to the lists made by J. Perrin Smith. "It 

 may be remarked, however," says Girty, ^''*' "that recent collections made in the 

 Carboniferous of Alaska are so suggestive of the fauna of the McCloud shale by 

 way of containing the same or similar species as to indicate the extension of this 

 fauna and, possibly, of the earlier Carboniferous faunas of the California province to 

 that region." 



A later article by Diller ^''^ gives detailed descriptions of the Bragdon formation 

 and cites paleontologic evidence of its early Carboniferous age, controverting 

 Hershey's conclusion that it was Jurassic. 



The latest description, comprising a summary of all the facts relating to the 

 Carboniferous of the Klamath Mountains, is given by Diller ^^^ in the Redding 

 folio. 



K 11. NEVADA. 



(See J 11 (Eureka district), pp. 364-366, and K 12 (Wasatch section), below.) 



K 12. WASATCH AND UINTA RANGES. 



The stratigraphic relations of the Carboniferous of the Weber Canyon section, 

 Utah, are thus described by King: ^^ 



Directly and conformably overlying the Ogden quartzite comes the great Wahsatch lime- 

 stone, which shows continuous outcrops for several miles and is thoroughly exposed from 

 summit to base, making a total single series of limestone of 6,500 to 7,000 feet., The most 

 valuable part of the whole Weber section begins with the bottom of this limestone, which rests 

 on a few thin sheets of olive-colored argiUites separating it from the Ogden quartzite below. 

 There seems to be no intercalation whatever of limy material at this point. The quartzite 

 comes up sharply to the argiUites, which are here not over 10 or 15 feet thick and give way 

 immediately to impure earthy limestones of a very dark color. Thus far, on this section, the 

 lower 1,200 feet of the Wahsatch have not yielded any fossils, but at the height of from 1,200 

 to 1,400 feet from the bottom of the limestone, in the neighborhood of Weber station, the hiUs 

 directly north of the depot are rich in Coal Measure forms. 



At Weber station the beds, which are about 1,300 feet stratigraphically above the base of 



the Hmestone, * * * are usually of quite pure limestone, and the strata vary in width from 



extremely thin sheets to heavy tables. So, too, they vary in their lithological condition, some 



being highly crystalline, others merely granular, and some even very roughly granular. 

 ******* * * 



Passing up the canyon, the series of limestones continues consecutively, without inter- 

 ruption, for 5 or 6 miles, exposing 5.000 to 6,000 feet in thickness above the depot. 



******** * 



