668 WHITMAN CROSS 
through the area now traversed by the Gunnison Canyon, where 
Mesozoic beds rest on the pre-Cambrian complex. This may be 
true, but it must be borne in mind that the pre-Dolores and pre-La 
Plata uplifts with their succeeding denudations may have removed 
the entire Paleozoic section from much of this tract. 
As distance from the mountain source of these clastic materials 
increases, the beds are naturally finer grained and grade into shales 
and marls, and correlation of widely separated sections becomes 
difficult. It is evident that the sub-Dolores and probably Paleozoic 
red beds need much closer study as to their structural relations to 
the overlying Triassic, as well as careful record of sections at favor- 
able points, before correlation can be made satisfactory. 
PENNSYLVANIAN SERIES 
Fossiliferous Carboniferous strata were found by Newberry in 
1859 in Grand River Canyon and in the lower part of Cafion Colorado. 
The section referred by him to the Carboniferous was described as 
follows in the “General Section of the Valley of the Colorado” 
(28, p, 99). 
14. Blue limestone, somewhat cherty. Fossils: Spirijer cameratus, 
FEET 
Athyris subtilita, Productus semi-reticulatus . 110 
15. Bluish-white, red, or mottled sandy limestone, with rine oh ted 
shale naire é B55 Cota: SR Maes 
16. Hard, blue cherty cata. recs same as No. LA Yop) "sero ths Se rah rape © 
17. Alternations of blue limestone, red and gray sandstone, to bottom of 
cahon . ; . 0 c A : c : : : : 5 dE {\SIo) 
On the map accompanying Newberry’s report the point at which 
he reached Grand River is located only about 6 miles above the junc 
tion with Green River, whereas according to the La Sal sheet of the 
U. S. Geological Survey, Cafion Colorado, the name of the side 
gorge descended by Newberry, joins Grand River Canyon at 9 miles 
below Moab and 24 miles above the union with Green River. Whether 
Newberry’s locality be near the junction of the Grand and the Green, 
or but a few miles below Moab, it is natural to assume that a fossilif- 
erous Pennsylvanian Carboniferous section discovered by us on the 
northwest side of Grand River, opposite Moab, is identical strati- 
graphically with some part of that found by Newberry. The faunal 
