A LIMNOLOGICAL STUDY OF THE FINGER LAKES. 
535 
end of Seneca Lake, a boring was carried down over 300 meters (1,000 feet) without 
reaching the rock, and similar borings at Ithaca have found loose material at greater 
depths than the maximum depth of Cayuga Lake. We are not aware that any similar 
observations have been made in the other valleys. 
Between the westernmost tributary of the Clyde River and the Genesee Valley are 
four short, steep-sided valleys, deeply cut into the highlands, which here extend well 
toward the north part of the plateau. Each of these contains a lake similar in form to 
the lakes of the Seneca Basin, but much smaller and shallower than any of these except 
one. The outlets of these lakes also flow north, but soon turn west and reach the Genesee 
River by a short course. 
In this district, therefore, lie ii larger lakes, each of them occupying a major valley 
in the north slope of the highlands (see fig. i), a valley which in all cases but one opens 
independently upon the front of the highlands. The northern ends of these lakes are 
near the north end of their respective valleys and, in general, are not far from the same 
latitude. This is especially obvious in the five lakes that occupy the central and larger 
valleys. To the south these lakes extend for a longer or shorter distance in proportion 
to their length, being longer in the center of the region and shorter, in general, toward the 
east and west limits. 
In the center of this district the relatively low land of the Seneca Valley extends 
southward in a broad lobe. In the two valleys of this region lie Seneca and Cayuga 
Lakes, nearly parallel to each other and of almost exactly equal length and area. They 
are by far the largest and deepest lakes of the series. East of Cayuga and west of 
Seneca lie two other major lakes, Owasco and Skaneateles to the east and Keuka and 
Canandaigua to the west. East of Skaneateles Lake lies a single lake, Otisco, much 
smaller and shallower than any of the six; while to the west of Canandaigua come 
Honeoye, Canadice, Hemlock, and Conesus Lakes, constituting the series of four small 
lakes belonging to the Genesee Basin. 
Thus the largest, deepest, and least elevated of these lakes lie in the center of the 
group. The elevation of the surface of the lakes increases in general from these toward 
the east and the west, declining somewhat at the extreme ends of the series. (See fig. 2.) 
The lakes which lie immediately east and west of Seneca and Cayuga are similar 
in depth, though not in area. Owasco is considerably smaller than Keuka, but each is 
between 50 and 55 meters in maximum depth. The two lakes which lie next to the east 
and west, Skaneateles and Canandaigua, resemble each other very closely in length, 
area, depth, and topographic surroundings. Two lakes 70 kilometers apart can hardly 
resemble each other more closely than do these. As the table shows, they are considera- 
bly larger and much deeper than Owasco and much deeper than Keuka, although smaller 
in area. These six major lakes, in spite of their differences, belong to the same general 
class, as is shown by their dissolved gases and temperature. The small lakes lying still 
farther to the east and west are lakes of a different class, as the same series of facts will 
show. None of them reaches 30 meters in depth, and in area the largest of them is not a 
quarter the size of the smallest of the major lakes. 
The ridges between these valleys rise in general to a maximum height of about 600 
meters (1,800 to 2,000 feet) above the sea or 300 to 400 meters (1,000 to 1,500 feet) 
