All this, however, goes upon the assumption that fish can hear, in
the proper sense of the word.  And this, it must be confessed, is an
assumption not yet fully verified.  Experienced anglers and students
of fishy ways are divided upon the question.  It is beyond a doubt
that all fishes, except the very lowest forms, have ears.  But then
so have all men; and yet we have the best authority for believing
that there are many who "having ears, hear not."

The ears of fishes, for the most part, are inclosed in their skull,
and have no outward opening.  Water conveys sound, as every country
boy knows who has tried the experiment of diving to the bottom of
the swimming-hole and knocking two big stones together.  But I doubt
whether any country boy, engaged in this interesting scientific
experiment, has heard the conversation of his friends on the bank
who were engaged in hiding his clothes.

There are many curious and more or less venerable stories to the
effect that fishes may be trained to assemble at the ringing of a
bell or the beating of a drum.  Lucian, a writer of the second
century, tells of a certain lake wherein many sacred fishes were
kept, of which the largest had names given to them, and came when
they were called.  But Lucian was not a man of especially good
reputation, and there is an air of improbability about his statement
that the LARGEST fishes came.  This is not the custom of the largest
fishes.