On Wednesday, relatives have invited me to accompany them to Shell Bluff along the Savannah River, home to the Dry Branch formation which is late Eocene (approx. 38 MYA) in age. This formation is home of an oyster bed, but not just any old oysters:     Enter Crassostrea Gigantissima, a YUGE prehistoric Oyster that can grow a whopping 20 inches long. That's almost as long as my forearm!    So how much do you guys know about these behemoths?