The shells found at
http://community.webshots.com/album/15635734DeXAOdskpF are:
Top row - the brachiopod Hemithyris psittacea Chemnitz (sorry i don't
have the date).
Second row: 1) sorry i don't do fresh-water beasties 2) Yoldia
hyperborea (A.A. Gould, 1841, ex Loven, ms.)  3) Macoma calcarea
(Gmelin, 1791)
Next two rows: Chlamys islandica
Last one: Astraea montagui (Dillwyn, 1817), i think: this family is
REALLY difficult (so don't believe the literature about distributions,
habitats, etc.!), and it didn't seem to be hooked up to the larger photo
very well.  Would help to have the size given, for unknowns, and basic
habitat data.

If anyone has specimens from the NW Atlantic, north of Cape Cod, that
need an ID, i'll gladly give it a shot.

From Indian Summerland,
Ross.