VEltMILLION GREEK BASIK 225 



away by erosion from the interior of the basin. Similar beds are observed 

 to form the crest of the ridge which separates the Yampa and White River 

 Valleys to the west of this point, where they are capped by a coarse con- 

 glomerate, which may possibly belong to the Wyoming Conglomerate. The 

 connection of these beds with the Tertiaries of the White Hiver Valley was 

 not traced, but their position on the ridge proves that there existed a former 

 connection between the Tertiary seas to the north and south of the Uinta 

 Mountains. It is well known that, in the White River Valley, a series of 

 calcareous shales, closely resembling lithologically those of the Green 

 River series, has been discovered, which contain the same abundant remains 

 of fish and insects that are characteristic of this group. The vertebrate 

 remains discovered in the beds of the Uinta Eocene by Professor Marsh's 

 parties are closely allied, as will be seen later, to those found in the Bridger 

 beds. It is probable, therefore, that a cpnnection once existed at this point 

 between the seas, in which these two series of beds were deposited, on either 

 flank of the range. 



Vermillion and Red Ceeek Basins. — In the basin of Vermillion 

 Creek, which is a region of flat terrace-like Tertiary benches, intersected 

 by a complicated system of dry water-courses, the beds of the Vermillion 

 Creek series have their greatest development. At the lowest portion of 

 the basin, the beds which immediately overlie the upturned Cretaceous are 

 a series of grayish-drab gravelly sandstones and clays, lying approximately 

 horizontal. They rise gently to the east and north, and extend high up 

 on to the northern flanks of the Owi-yu-kuts Plateau. The higher beds, 

 exposed in the canons of the western fork of Vermillion Creek, are coarse 

 sandstones and gravels, which, in the upper portion, have the character- 

 istic red color of this formation. It was on one of the broad benches 

 between the branches of this creek, to the east of Ruby Gulch, that the 

 originators of the famous diamond fraud of the summer of 1872 located 

 their supposed discovery. An exposure of coarse iron-stained sandstone, 

 on the surface of the mesa at the foot of Diamond Peak, was strewn by 

 them with rough diamonds and rubies, which were ingeniously mixed with 

 the soil around, so as to make it appear that they came from the decom- 

 position of the sandstone. In the bluffs near this point, a few remains of 



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