But higher up there are small, imperfect, transverse moraines, made during the subsequent retreat, behind which water has collected, forming lakes and marshes.

But observe: these moraines are also _in the vicinity of a great lake_; and we have abundant evidence, in very distinct terraces described by Whitney[4] and observed by myself, that in glacial times the _water stood at least six hundred feet above the present level_.

In fact, there can be no doubt that at that time the waters of Mono Lake (or a much greater body of water of which Mono is the remnant) washed against the bold rocky points from which the debris ridges start.

_The glaciers in this vicinity, therefore, must have_ run out into the water six or seven miles, and doubtless formed icebergs at their point, and, therefore, formed there no terminal moraine.
[Footnote 4: _Geological Survey of California_, Vol.

I, 451.] That the glaciers described about Lake Tahoe and Lake Mono ran out far into the water and formed icebergs I think is quite certain, and that parallel moraines open below are characteristic signs of such conditions I also think nearly certain.
_f.