THE UPPER CRETACEOUS OF KANSAS. 
INTRODUCTION. 
BY ERASMUS HAWORTH. 
At the close of the Comanche period, already described by Pro- 
fessor Prosser, the outlines of the North American continent were 
well formed and were similar to the continent as now known ex- 
cepting a narrow inland sea reaching from the southern part of the 
United States to beyond the limits of Canada, and probably con- 
necting with the Arctic ocean. This inland sea separated the east- 
ern part of the American continent from such portions of the great 
Cordilleras area as were elevated into dry land. The coast lines 
along the Atlantic coast and the Gulf of Mexico were considerably 
farther inland than they are at present, leaving a border averaging 
from a hundred to a hundred and fifty miles in width, which has 
since been elevated and has become a part of the continent. Plate 
XXV,a small sized map of the United States, has the approximate 
areas marked on it which were under water at the close of Comanche 
time and which subsequently had Cretaceous rocks formed over 
them. It will be seen that there was an arm of the ocean reaching 
northward from the western part of the Gulf of Mexico, passing 
through Texas, the Indian Territory, Kansas, eastern Colorado, 
Nebraska, the Dakotas, eastern Wyoming, and Montana. The same 
area probably reached far into Canada, or quite likely connected 
with the Arctic ocean. Throughout this relatively large area sedi- 
ments were accumulating from the drainage of the dry lands on 
either side, and from the accumulation of matter from animal organ- 
isms, so that heavy deposits of sandstones, limestones, and shales 
were formed. These deposits are similar in many respects to those 
formed during the same time along the ocean borders of the Atlantic 
and the Gulf of Mexico. 
Western Kansas and eastern Colorado represent the great central 
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