staxton] NORTHERN UTAH. 39 



Feet. 



8. Massive gray and yellowish sandstone forming the third ridge, with Os- 



trea soleniscus, Pholadomya subventricosa(l), Cardium, and a few other 

 marine Cretaceous species 200 



9. Mostly covered, but evidently underlain by shales and soft sandstone. 



A band of sandstone about the middle of this member yielded speci- 

 mens of Mactra, Cardium, and Pecten. Thickness about 1, 500 



10. Gray and brownish sandstone, with bands of shale. The upper 30 feet 

 is a massive, irregularlj" bedded brownish sandstone with many speci- 

 mens of Inoceramus erectu8 } Cardium, Osirea, and a few other species 

 mostly in the form of casts 150 



The beds above this horizon are shown by the few exposures to con- 

 sist of shales and beds of soft coarse sandstone with bands of con- 

 glomerate in the upper portion. I estimate that there is room for 1,500 

 feet of strata below the Tertiary Echo canyon conglomerate. 



From No. 2 to No. 10, inclusive, the strata were measured by means 

 of a clinometer compass in the manner described by Mr. O. D. Walcott. 1 

 The thicknesses given are therefore reasonably accurate, the principal 

 source of error being the possible variations in dip within the long 

 covered spaces. 



The following species have been found in No. 1 of the section: 



Ostrea soleniscus. Gyrodes depressa. 



Modiola multilinigera. Amauropsis coalvillensis. 



Inoceramus labiatus. Glauconia utahensis. 



Barbatia micronema. Turritella micronema. 



Trigonarca obliqua. Neritina pisum. 



Cardium pauperculum. Neritina patelliformis. 



Mactra utahensis. Chemnitzia coalvillensis. 



Mactra emmonsi. Eulimella funicula. 



Parapholas sphenoideus. Admetopsis rhomboides. 



Siliqua huerfanensis. Admetopsis subfusiformis. 

 Corbula nematophora. . Fnsus gabbi. 



No fossils have been found in the lower 300 feet of the section, and 

 nearly all of those above enumerated occur in a zone from 100 to 150 

 feet below the principal coal bed. Several of the species are very 

 abundant in certain layers of the sandstone. 



The thin bed of sandstone immediately above the coal is usually bar- 

 ren of fossils. The only species that have been observed in it are Ostrea 

 soleniscus and Inoceramus labiatus. The overlying thick bed of soft 

 shales constituting the larger part of No. 2 is seldom seen in natural 

 exposures but two or three shafts have been dug in it while prospecting 

 for coal and the shales thus thrown out show large numbers of Inocer- 

 amus labiatus. 



Certain bands in the heavy bedded sandstone of No. 3, especially 

 near the top, are very fossiliferous. At Coalville this bed is repeated 

 by a fault so that it forms the first and second ridges, but in addition to 

 the structural evidence of the presence of a fault the fossils plainly 

 show the repetition. On Grass creek, about 4 miles from Coalville, this 



^roc. IT. S. National Museum, Vol. xi, 1S88, p. 447. 



