Others are obliterated by
land-slips, earthquake taluses, etc., but these lake-deaths compared
with those resulting from the deliberate and incessant deposition of
sediments, may be termed accidental. Their fate is like that of trees
struck by lightning.
The lake-line is of course still rising, its present elevation being
about 8000 feet above sea-level; somewhat higher than this toward the
southern extremity of the range, lower toward the northern, on account
of the difference in time of the withdrawal of the glaciers, due to
difference in climate. Specimens occur here and there considerably below
this limit, in basins specially protected from inwashing detritus, or
exceptional in size. These, however, are not sufficiently numerous to
make any marked irregularity in the line. The highest I have yet found
lies at an elevation of about 12,000 feet, in a glacier womb, at the
foot of one of the highest of the summit peaks, a few miles to the north
of Mount Hitter. The basins of perhaps twenty-five or thirty are still
in process of formation beneath the few lingering glaciers, but by the
time they are born, an equal or greater number will probably have died.
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