Is this Ostrea edulis?

[paul monfils]

The three common Ostrea/Crassostrea species in that locality - edulis, gigas, and virginica - can be difficult to separate because they are so variable in shape.  However, usually the interior of O. edulis is completely white, including the muscle scar, while the other two species have the dark purple muscle scar.  C. gigas is usually quite elongate, especially when young.  So, I believe this is Crassostrea virginica, a species that is also very common here in the N.E. United States.