When in Hawaii in the 50's I was convinced that small Cypraea isabella
were from deep water and larger ones from shallow water.  When
transfered to Boston, I had time to sort the specimens in various ways.
 They did make groups by depth (though the depths compared were 50 to 90
feet vs 4 to 40 ft.  However, when sorted by collecting area, the groups
were more definite as to NW Oahu vs SW Oahu using the same shells.

A number of other species such as Conus pennaceus, particularly those
with a short veliger stage vary considerably in shape, size and color in
different areas, and even have different times for egg laying.  Oliva
paxillus sandwichensis form fairly tight colonies of similar shells with
light shells found in one type of sand and dark shells in another.  This
seems to indicate a tight genetic group.
--
                     Aloha from Wesley M. Thorsson
Editor of Internet Hawaiian Shell News, a monthly Internet Publication
           122 Waialeale St, Honolulu, HI  96825-2020,  U.S.A
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