I hope the list will forgive me asking a question i could find an
answer to with a bit of digging on my own, but hopefully it will be of
interest to others on the list who may have been wondering about the
same thing!

        The genus Scaphander often has curious "auxillary plates" inside, whose
function is not immediately obvious: what DO their owners use them for,
and do all Scaphander have them in some form or another, or just some
species of this curious genus?

From the again-wet (but still great!) North,
Ross.