2^2 
IOWA ACADEMY OP SCIENCE 
too slight for the evidence of it to persist. The steep ends of 
the low divides a mile west of Valley Junction are in themselves 
ijot satisfactory evidence of an old shoreline; and nowhere else 
is any evidence noted JhOt the flat- on which" Valley Junction is 
located is the old bed of ponded water. The border line between 
the flat with sand and gravel beneath it to a depth of at least 
thirty feet (at the pumping station of the Valley Junction water 
plant) and the low upland present an appearance of conditions 
similar to those observed in areas of Kansan drift further south. 
With absence of distinct evidence of ponding, this flat must be 
considered a portion of the terrace found along the rivers. The 
origin and age of this terrace I now wish to consider in a sepa- 
rate paper on that subject. 
