320 OLDER MESOZOIC FLORAS OF UNITED STATES. 
Smithsonian Institution, which the latter had referred to me. On 
stating my intention to visit the region, I was requested, and subse- 
quently instructed, to collect data and make a report covering both 
the scientific and the practical aspects: This I did, and my report 
was submitted to the Director of the United States Geological Survey 
on December 12, 1899." 
An account of the results of my operations in this field will have 
a considerably broader scope than that of the report just mentioned, 
as they covered a large amount of territory more or less remote from 
the region popularly known as the petrified forests, extending as far 
west as Supai, and north to the Grand and Marble canyons, including 
an expedition down the Litttle Colorado on its right bank to ane cross- 
ing of the Lee’s Ferry road, 70 miles below Winslow. 
Owing to the almost entirely volcanic character of the great region 
occupied by the Bill Williams Mountain, San Francisco Mountain, 
Kendricks Peak, and the Elden Mesa, it was impossible for me in so 
short a time to work out the stratigraphy of that region, but that there 
are Triassic remnants in it seems certain. Petrified wood was found 
at the most westerly point examined, viz, a mile northwest of Supai. 
I was informed from a reliable source that large silicified logs occur 
8 miles west of Williams. 
The Colorado Plateau to the north, as is well known, is occupied by 
Carboniferous limestone, and this extends eastward to near the Little 
Colorado. Dr. Newberry observed that this limestone— 
descending from the San Francisco Mountain, * * * showed a dip to the 
northeast of at least 100 feet to the mile; and before reaching the [Little Col- 
orado] river it passed under beds of red shale and sandstone, which are conformable 
with it. This sandstone is deep blood red in color, is soft, and eroded into fantastic 
blocks and masses, of. which the surfaces are most curiously etched and carved by 
weathering. Above these heavier beds are soft, red, argillaceous shales, with layers 
of red and green, foliated, ripple-marked, fine-grained, micaceous sandstones, all 
without fossils. Such is the geology of the south bank of the river. On the north 
bank the red shales appear at intervals, but are usually concealed by alluvial soil, 
sand, and gravel. About 7 miles from the river the valley is bounded by a mesa 
wall nearly 1,000 feet in height, of which the base is formed by the red shales and. 
sandstones before described.” 
The party were then on the northeast side of San Francisco Moun- 
tain, and the Permian beds are reached some distance southwest of the 
Little Colorado. On the south side of the volcanic area, the principal 
vents of which formed the San Francisco and Kendricks peaks, Mount 
Sitgreaves, the Elden Mesa, and Bill Williams Mountain, no one seems 
to have reported any sedimentary strata higher than the Upper Carbon- 
1Report on the Petrified Forests of Arizona, by Lester F. Ward, Paleontologist, U. S. Geological 
Survey; Department of the Interior, Washington, 1900; 23 pages, 8°. 
2Report upon the Colorado River of the West, explored in 1857 and 1858 by Lieut. Joseph C. Ives, 
Washington, 1861, 4°. Part III, Geological Report, by J. 8. Newberry, p. 75. 
