I20 WHITMAN CROSS 



fragmentary condition of the remains and the rarity of determinable 

 specimens is, however, entirely analoguous with the occurrence of 

 similar material in the Dolores beds in Colorado. 



Poorly preserved Unios are common in the Dolores formation 

 and we observed very similar undeterminable shells in the conglom- 

 erate with bone fragments, at Moab. Three species of Triassic 

 Unios in a much better state of preservation were found some 

 years ago on Grand River very near the Vermilion Cliff sandstone 

 by L. M. Prindle (5, p. 653), and there is no basis for doubting that 

 they came from the bone-bearing series of beds. 



With this knowledge of the Moab and Grand River sections, it 

 seems almost certain that the ninety-two feet of strata embraced 

 under No. 11 of Newberry's section represent the series of bone- 

 bearing conglomerates, etc., which we refer to the Dolores formation. 

 The absence of the gypsiferous shales and of the overlying conglom- 

 erates, sandstones, and shales, indicates a stratigraphic break in 

 Newberry's section and the probable horizon of the break is beneath 

 No. II. 



Uinta Mountains. — The statements of Powell and Dutton that 

 the Shinarump Group is typically developed on the flanks of the 

 Unita Mountains are without confirmation in the descriptions of the 

 strata referred to the Triassic by these authors or the geologists of 

 the Fortieth Parallel Survey. Powell refers 1,095 ^^^^ ^^ beds west 

 of Flaming Gorge to the Shinarump and describes them briefly as 

 follows: "Shales and sandstones containing much gypsum; weather- 

 ing in many colors, but brown and chocolate tints prevailing; in 

 many places constituting bad-land beds" (23, p. 152). There is 

 no suggestion of the Shinarump conglomerate in this section. 



It is clear that Powell included in the Shinarump of the Uintas 

 the beds called Permo- Carboniferous by the Fortieth Parallel geolo- 

 gists, and Permian by Dutton in his Grand Canyon monograph, and 

 the description above cited seems to apply to those strata. There 

 is no known evidence that the fossiliferous horizon found at Moab is 

 present on the Uinta slopes, but the discovery reported by Williston 

 (28) of a Triassic vertebrate fauna in Wyoming closely related 

 to, if not identical with, that from the Little Colorado Valley and the 

 Dolores formation makes it not improbable that closer study will 



