Shell Specimen: Sea Urchins and Sand Dollars
“Shelling” is a fun for professional scientist and amateurs alike. A majority of the shells below are composed of the mineral aragonite CaCO3. Many of my modern or “recent” shells have fossil relatives in my Fossil Gallery. Below I have organized images and data of some of my sea shells.
Special thanks to Tina Petway, Lucy Clampet and Gary Kidder for giving me what I could not find.
Kingdom: Animalia – Phylum: Echinodermata – Subphylum: Echinozoa – Class: Echinoidea – Superorder: Echinacea – Order: Echinoida
(sea urchins)
Late Cretaceous to Holocene

Sea Urchin

Sea Urchin

Sea Urchin

Sea Urchin (complete)

Sea Urchin Spines

Sand Dollar “Teeth”
Kingdom: Animalia – Phylum: Echinodermata – Subphylum: Echinozoa – Class: Echinoidea – Superorder: Gnathostomata – Order: Clypeasteroida
(sand dollars)
Late Paleocene to Holocene

Sand Dollar

Sand Dollar

Sand Dollar

Sand Dollar

Sand Dollar (with soft tissue)

Sand Dollar
Data: Dance, S. Peter, Smithsonian Handbook: Shells, The photographic regognition guide to seashells of the world. A Dorling Kindersley Book.