342 EXPLORATIONS ACROSS THE GREAT BASIN OF UTAH. 



In some masses of very hard, light-gra yish, compact, silico-calcareous rock from 



loid shells ivscn.bliug the Permian genus Uahrrllhi .- also fragments of a coral similar, 

 as far as can be determined, to the genus Phylfopora of Kino-. From the analogy of 

 these fossils t<> Permian forms, and the fact that the bed in which they occur holds a 

 higher' stratigraphical position, as I am informed by Mr. Engelmaun, than the dark 



there would appear to be some reason for thinking there may be here a representation 

 of the Permian. This supposition would also seem to receive further support from the 

 occurrence at localities not far east of this of Jurassic, and probably Triassic, deposits ; 

 still it would be unsafe without more reliable evidence to refer these fossils to the Per- 



There are in the collection from localities in Eastern Kansas, near Cottonwood 

 ('reek, on the north side of Kansas River, several specimens of yellowish magnesian 

 limestone, containing apparently the same species of Pseudomonotis, Avictthpcctrn, 

 BakeveUia, Mi/alum, etc., known to occur at many places in the eastern part of that 

 Territory, in strata that have been referred to the Permian system. As there is, how- 



whether the particular outcrops from which they were obtained should In- classed with 

 the Permian or the I'pper Carboniferous, though they most probably belong to the 



The farthest western locality at which specimens were collected indicating the 

 occurrence of Jurassic rocks is on the east side of the Wahsatch Mountains (lati- 

 tude, 40° 48' north, longitude, 111° 15' west). They consist of gray, argillaceous, 

 more or less sandy rock, containing fragments of Pecten, Ostrea, and stems of Penta- 

 crinus, which latter agree exactly with those of P. asteriscus, Meek and Hayden, from 

 the Jurassic beds at the Black Hills, Dakota. The strata containing these fossils are 

 associated, as I am informed by Mr. Kngelmann, with a series of light-colored and 

 reddish sandstones. 



At lied Buttes, on the North Platte, above Fort Laramie, well-marked Jurassic 

 fossils were also collected, in gray argillaceous sandy beds. They consist of frag- 

 ments of the same Prutucrimts mentioned above, and an Oyster, nearly related to 0- 

 Marsha and Grypheaa calceola, Qnenstedt, or an allied species, anew species of Pecten, 

 near P. km* of Sowerby, and Belemnites densu*, Meek and Hayden. 



The strata from which these fossils were collected are clearly of the same age as 

 the Jurassic outcrops at the so„thwe>t ba<e of the Black Hills, and, as at that place, 

 hold a position above a series of red arenaceous deposits containing large quantities 

 of gypsumf 



A few fossils of Cretaceous age were found as far west as Bear Eiver, and on 



