Anyone going to Cape Cod should make every effort to shell BOTH sides-
they wil be amazed at the difference in faunal assemblages!!  The Gulf
Stream is deflected ont to sea by this prominance, which juts out and
acts as a barrier separating  the cold waters in the Gulf of MAine
(influenced by the Labrador Current) and the warmer, Gulf-Stream- bathed
waters to the south (in the same manner as Cape Hatteras does further
south).  The difference in molluscan fauna is quite striking, and should
be experienced first hand.  Look under rocks, in grasses and seaweed, by
boulders, in kelp holdfasts washed ashore, in subtidal seds (bring a 1mm
(24-mesh) screen if possible), etc.  Have fun!!
                                                                                                -Ross M.