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Various

"Scientific American Supplement, No. 324, March 18, 1882"


Some fishes and reptiles are hibernaters. Frogs and toads sleep out the
winter at the bottom of ponds or in holes in the ground. Tree toads, if
kept in a cage in the winter and provided with soil, will endeavor to
cover themselves with it, showing how strong the instinct or habit
is. Some fishes are so insensible to heat or cold that when in this
condition they can be frozen and carried for a number of days and then
be brought back to an active condition. The pond snail passes into a
winter sleep as soon as the temperature of the water is below 14 deg. Cent.,
that is, they will not digest food or grow until the temperature of the
water is at least up to 15 deg. Cent. Those who have watched the Harlem
River from McComb's Dam Bridge cannot have failed to notice the curious
appearance of the muddy shores of the river and creeks at low tide.
If the sun shines brightly, the dismal beach seems to quiver and
scintillate in a most beautiful manner, reflecting the light like so
many diamonds. If we draw nearer, this shore is seen to be entirely
covered in places with little snails, that, left by the tide, are
forging through the mud to regain the water, and the sunlight striking
on them is reflected by the glass-like secretion with which they are
covered, producing the curious effect noticed.


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