Physical 

Slipper Shells are off-white and bumpy, and grow no larger than 3.8 cm.  They are univalves with a bottom plate that covers almost half of the ventral surface of the shell. There are three species found locally.

Image by Sytske Dijksen and Ecomare, courtesy of Wikimedia

Habitat

Crepidula sp. attach to and grow on any available hard object.  They can be found on the shells of invertebrates, pilings, and boat bottoms.

Feeding 

Like most gastropods, Crepidula sp. filter feed, and collect food using their cirri.