An oddly shaped shell often found in batches.
A great number of pen shells (brown) washed up after a small storm on Sanibel.
Many other shells also washed up, (white and other colors) mostly bivalves.
A few stiff pen shells washed up on the beach.
After storms many hundreds get washed up.
A group of marine bivalves from the beach drift on West Gulf Drive Beach, in Sanibel.
In the central part of the image, the single valves that are cupped, hemispherical and yellow on the inside are buttercup lucines.
A right valve of Chionopsis intapurpurea, common name the "lady-in-waiting venus".
Viewed from above to show the lunule.
A juvenile left valve of Mercenaria campechiensis, showing the lunule.
picked up on an Atlantic coast beach in NJ as a souvenir
Collected on Cape May beach, NJ - Souvenir
Bivalvia is a class of marine and freshwater molluscs with laterally compressed bodies enclosed by a shell in two hinged parts. Bivalves include clams, oysters, mussels, scallops, and numerous other families of shells. The majority are filter feeders and have no head or radula. The gills have evolved into ctenidia, specialised organs for feeding and breathing. Most bivalves bury themselves in sediment on the seabed, where they are safe from predation. Others lie on the sea...