Dear Moshe;
        I would not worry too much about the various so-called "forms" of
Buccinum undatum. Like most Buccinids, it is immenseley variable in
shape, but as with many of this family, very few of the variations
seem to have anything to do with environmental factors - ie, they are
not ecophenotypes, and therefore have little  or no taxonomic
validity, and are of interest mainly to collectors, most of whom like
to acquire various forms and varieties of species, whether they are
named or not.  With Buccinids, it is often difficult to distinguish
between the various forms, as they intergrade smoothly, and the
origional descriptions are seldom entirely satisfactory!!
Cheers,
Ross.
--
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