Just one note concerning Janthina. They are supposed to live in
rather large numbers in Mare Sargassum, an area in the Atlantic Ocean
which has little movement of its waters, allowing surface plants and
animals  a place to live from which they will not be torn by air and
water currents. I imagine there has been some work published on the
inhabitants of this area. It would be interesting to know what sea-
weeds live there and what mollusks live on the weeds.
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