It also shares the petal-like pattern both inside and out of other sand dollars. This same pattern and spiny-ness is also shared by sea urchins, another echinoderm that lives in Maine.

CORPUS CHRISTI, Texas — Beachcombing for seashells, sea glass and sand dollars is a popular hobby on the Texas coast. But Jace Tunnell is more interested in the weird stuff that washes up on ...