Is this the same way of seeing that octopus and squid sense colour and
respond with changing their own  colour?

-----Original Message-----
From: Conchologists of America List [mailto:[log in to unmask]]On
Behalf Of Thomas E. Eichhorst
Sent: Saturday, 10 May 2003 3:41 AM
To: [log in to unmask]
Subject: Re: eyes


Art -

Can't say much about all mollusks, but I can say that some gastropods "see"
through their skin.  Tests on Nerita picea Recluz, 1841 (an Hawaiian and
Johnson Island endemic nerite) demonstrated a response to shadows generated
by dark pigmented areas on the dorsal portion of the foot of the animal.
These are usually longitudinal, irregular, dark stripes and are found in
quite a few gastropods.  In other words, even though the animal has two eyes
(which also react to shadows) it also sees with its skin!  The same dermal
shadow response has been recorded in Nassarius reticulata (Linnaeus, 1758)
and the garden slug Arion ater.

Tom E.