Mesozoic and Cenozoic Geology and Paleontology. 123 
The Brown’s Park Group occupies that expansion of Green river 
valley which is known as Brown’s Park. From there it extends east- 
ward and around the eastern end of the Uinta uplift, except a few miles 
interruption of its continuity there, and thence extends westward 
along the southern base of the Uinta mountains a large part of the 
length of thatrange. It extends northward from the eastern portion 
of the Uinta mountains, as far as Dry mountains and Godiva ridge. 
Remaining patches of it show that the formation formerly extended 
eastward as far as the foot hills of the Park range. It occupies nearly 
the whole surface of the western portion of Axial basin, comparatively 
small areas immediately east and immediately north of Yampa moun- 
tain, and a considerable portion of the space between Junction moun- 
tain and the eastern end of the Uinta uplift, all of which spaces are in 
unbroken continuity. It, also, occupies a large space from Raven 
ridge and Red Bluff Wash extending far westward. 
F, M. Endlich observed the Wasatch and Green River Groups 
spread over an area in the White river region of western Colorado, of 
more than 3,000 square miles. A section on Douglas creek, a branch 
of White river, showed a thicknesss of 1,500 feet for the Wasatch 
Group. A’stratum of brick-red sandstone, 160 feet in thickness, and 
placed immediately below the middle of the Group, served as a land- 
mark for identification. Inferior beds of coal occur in the upper part 
of the Group. Groups of columnar monuments, and monuments 
composed of shales with cappings of sandstones are not uncommon. 
Fine exposures of the Green River Group occur in the Book Cliffs, 
just north of the Grand river. Geognostically and lithologically 
_ speaking, it is separable into an upper and lower division: The lower 
arenaceous division having a thickness of 2,400 feet, as obtained from 
the southern bold escarpment of the plateau, and corroborated by 
observations elsewhere ; and succeeded by laminated shales, having a 
thickness of 1,000 to 1,200 feet; the upper division consisting of 
yellow and brown sandstones, with thin interstrata of dark shales, and 
having a thickness of 1,100 to 1,200 feet. These sandstones, by ero- 
sion and weathering, have assumed many fantastic shapes, some imi- 
tating the ruins of some ancient building, and others rising in spires 
for several hundred feet above their gently sloping surroundings, <A 
group of three of these weathered monuments near Asphalt Wash, in 
White river valley, one of which is 80 feet high, received the name of 
the “ Happy Family.” 
On the White river drainage he observed no evidence pointing to the 
