1895.] NEW YORK ACADEMY OF SCIENCES. 51 
Mr. Winslow’s final report upon the Coal Measures of 
Arkansas is still unpublished, but he has given me his table of 
succession, which is as follows: 
I. Poteau Stage, 3300’-3900’, consisting mainly of shale, the 
Poteau shale. This interval contains several coal beds, that 
mined at Huntingdon and neighboring localities in northwestern 
Arkansas being the most important and near the base. 
II. Sebastian Stage, consisting of 
a. Greenwood sandstone, 100’, seen in Indian Territory, 
just south from Jensen on St. Louis and San Francisco railroad. 
b. Tomlinson shale, 500’—600’. 
c. Hartwell sandstone, 0’-100’, not present in Indian Terri- 
tory. 
eer. Belva shale, 0’-500’, not present in Indian Territory. 
e. Ozark sandstone, 0’-500’, not present in Indian Terri- 
tory. 
III. Spadra Stage, 0’-500’, consisting of shales and sand- 
stones with several coal beds, the semi-anthracites referred to 
long ago by D. D. Owen and recently described in Winslow’s 
preliminary report on the Arkansas coals. These beds thin 
westwardly and are wanting at the Indian Territory line. 
IV. Norristown Stage, usually consisting of two sandstones, 
the upper, from 0’—200’ and the lower, 100’-200’. At the line 
of Indian Territory, it is represented by one sandstone, 100’ 
thick. 
V. Booneville Stage, consisting of shales and from 400’—2500’. 
It contains coal beds, one below the middle and the other near 
the base. 
VI. Appleton Stage, consisting of 
a. Cross Plains sandstone, 50/-150’. 
b. Russellville shales, 500’-600’, with thin coals near bottom. 
c. Washburn sandstones, 500’—600/. 
VII. Danville Stage, not differentiated. 
The base of the coal measures was not reached in the area 
studied by M. Winslow, and the beds of the Danville Stage were 
not measured. 
The continuity of the series into Indian Territory is clear 
even to one traveling on a railroad train, but the erosion is so 
great that details of succession can be obtained only by patient 
study supplemented by records of boreholes. The sandstone 
ridges separated by swales marking areas underlain by shales 
are easily followed, and their curves exhibit well the structure of 
the region, while they afford the means of determining the place 
of the several coal beds. Dr. H. M. Chance spent several 
months of 1890 in studying the region along the line of the 
