240 Keyes—Stratigraphy of the Kansas Coal Measures. 
emphasis is placed on the fact that in passing from the east to 
the westin Kansas the observations made are not in aecord 
with those of Missouri and Iowa. In going in that direction— 
west—they most assuredly would not. ‘That would be about 
the same as if the sections in Lowa were constructed in a some- 
what north and south direction or in a way that would be par- 
allel to the ancient shore-line instead of at right angles to it. 
In eastern Kansas the original seaward slant of the beds was 
evidently to the northwest and a little farther to the west it 
was perhaps more nearly northward. In the states of Iowa 
and Missouri the observations were made from very different 
points of vantage—from the east or north sides of the bay-like 
expansion. More specifically, in looking towards the sea, 
straight out from the shore, the direction in northern Lowa 
would be to the south or southwest; in southern Lowa and north- 
ern Missouri directly west; in southwestern Missouri north- 
west. The reason is this: the Western Interior coal basin 
occupied a broad shallow depression, and the Carboniferous 
waters consequently filled a wide semi-circular bay opening to 
the westward. q 
In the Iowa report it is not stated, as is set forth in the 
recent paper, that the coastal area was a region of greater 
subsidence than the oceanic. - Nothing is said specifically 
regarding the relative rates of uprising or downsinking of the 
two districts; but it is stated that the oscillations affected very 
wide areas, and even, perhaps, approached in character conti- 
nental elevation and depression. Of course considerable stress 
was placed upon the movements of the shore lines; for the 
reason that these are the present measures of the changes of 
the sea with reference to the land. The area being so broad 
and so shallow was particularly susceptible to all changes of 
relation between the land and water; and comparatively slight 
vertical movements would have produced great alterations in 
the extension of the sea. 
Lately it has been conclusively shown that during the latter 
part of the Lower Carboniferous (Mississippian) the Interior 
basin was an area of uprising. The old shore must have 
extended from the present northwest corner of Iowa in a 
curved line through Des Moines, Kansas City and southwest- 
ward through Kansas into Oklahoma territory. It probably 
even extended farther to the west, but of this there is no evi- 
dence at present. At the time of greatest depression, or when 
the sea encroached most on the land, the border line was 
extended eastward to beyond the present position of the Mis- 
sissippi river and from St. Louis extended southwestward over 
a considerable part of the area now forming the northwestern 
flank of the Ozark uplift. Even during the deposition of the 
