384 REPORT UNITED STATES GEOLOGICAL SURVEY. 



10. Eongli-bedded, qiiartzitic sandstone, forms coping of sliarjp trans- 

 verse ridge, 100 to 200 yards south of No. 5. 



11. Slope, witli obscurely exposed limestone beds. 



12. Gray, brown- weathered, fine-gTained, gritty deposit, forming crest 

 of prominent bench about 200 yards soutli of No. 10. Dip 35° to 45° S. W. 



13. Gray limestone immediately overlying the preceding gritty bed, 

 with numerous casts of a small Lamellibranch shell, Pleuropliorus f 



14. Unexposed, 100 to 150 yards. 



15. Eusty-gray shaly limestone, 15 feet exx)osed ; dip 38°, S. 35° W. 

 IC. Brown arenaceous shales and dark gray limestone, obscurely ex- 

 posed in slope, 100 yards or more. 



17. Dark bluish-gray shaly fragmentary limestone, 20 feet exposed. 



18. Unexposed, slojje 100 yards or more. 



19. Heavy and thin-bedded, gray, rusty brown, buff limestones with 

 shaly grit bands, outcropping in southerly flank of prominent trans- 

 verse ridge over a space 100 to 150 yards 5 dij) 35°, S. 40° to 45° W. 

 Fossiliferous layers through this deposit from base to top, the forms 

 being the same throughout. These consist of, at least, two species, one 

 a medium-sized Aviculo2)ecten, and the other ai^pears to be referable to 

 Pseudomonotis^ the former occurring in abundance, but their state of 

 l)reservation is less perfect than could be desired. 



20. Southerly slope into dip sag, 200 to 400 yards, partly over the 

 ujjper vshaly limestone layers of the i:)receding bed. 



21. Eed shales and arenaceous deposits, more or less clearly exposed 

 in steep ascent rising into the main crest, 1,000 to 1,500 yards north of 

 the outlying ridge at bed No. 19. In the crest the tilted edge of a hea^y 

 ledge of red sandstone appears, dipping conformably with the uuderlymg 

 deposits, south west ward. 



The ridge last mentioned under No. 21 of the above section attains an 

 elevation of 2,200 feet above the Snake, or an actual altitude of 7,000 feet. 

 The " red beds" of which it is composed are seen to reach an enormous 

 development in the ridges lying to the south-southeast in the direction 

 of Station XXV, four miles distant. From the latter locality, and 

 probably higher position in the series, Mr. Klibel kindly brought in 

 specimens of dark red, even, thin-bedded sandstone, which he reported 

 as occurring in heavy ledges in the summit and along the crest of the 

 front spur, Avhere they also dip off to the southwest. The lower horizons 

 of the section furnish typical exhibitions of the Carboniferous lime- 

 stone series, but that part Avhich is of most interest is included in the 

 limestone seiies Nos. 13 to 19. These deposits reach a thickness of sev- 

 eral hundred feet, and might even attract the attention from the dissimi- 

 larity in their lithology as compared with the inferior limestones and 

 siliceous horizons. But the fossils contained in these upper limestones, 

 though api)arently few in species, offer, both in their specific affinities 

 if not identity, and their abundant prevalence in individual numbers, 

 so striking resemblance to the Permo-Carboniferous of other regions as 

 to leave little room to doubt that they represent the latest epoch of the 

 Upper Carboniferous x^ei'iod in this quarter. In regard to the red are- 

 naceous deposits and sandstones, which are apparently conformably 

 superimposed on the latter beds, their identity with the Triassic "red-bed" 

 series is conclusively proven both by their lithology and relative position. 

 The great development of these deposits in the vicinity of Station XXV 

 contrasts with their probable mu(ih less vertical extent in the belt outlying 

 Station XXIV, 10 miles to the northwest, though this may prove to be 

 more apparent than real. Yet it may be that the red sandstones in 



