KETTLES IN GLACIAL LAKE DELTAS. 
Tue object of this brief paper is to describe a remarkable 
basin in a glacial-lake delta in western New York, and to discuss 
similar phenomena in general only so far as to throw light upon 
this particular case. 
Between Canandaigua and Seneca valleys lie three north 
and south valleys which hold no lakes. The most westerly of 
these is the Middlesex or West River Valley, which drains south 
‘nto the head of Canandaigua Lake. The next is the valley of 
Flint Creek, which flows north. Eastward is another deep val- 
ley which drains south into Keuka Lake, at Branchport. Upon 
the west side of the middle one of these three lakeless valleys, 
the Flint Creek Valley, lies the little village of Potter. Close 
behind the village is a conspicuous plateau of stony gravel 
rising 250 feet above the valley plain. In the middle of this 
ancient plain occurs the singular basin herein described. 
This delta is one of the many phenomena which record the 
‘ntricate and interesting history of the glacial waters in the 
“Finger Lake” region. The events leading up to its formation 
seem to be as follows: During the recession of the front of the 
ice-sheet there came a time when the southern or upper end of 
each north-sloping valley was free of ice, and the impounded 
waters were forced into southward flow.* 
In the Keuka Valley the glacial waters were at first com- 
pelled to overflow directly south into the Cohocton River at 
Bath, but they soon found a somewhat lower outlet across the 
eastern rim of the basin through the site of Wayne village and 
the chain of small lakes. These waters have been named the 
«Presented before the American Association for the Advancement of Science, 
August 25, 1898. 
2 Papers descriptive of the glacial lakes of western-central New York may be 
found in the Bulletin of the Geological Society of America, Vol. VI, pp. 353-374: Vol. 
VII, pp. 449-452; Vol. VIII, pp. 269-284. 
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