Err

Sand Dollar, Sea Urchin, from Baja, California, U.S.A. (No.96)

£ 10.00
Add to cart
Sand Dollar, Sea Urchin, from Baja, California, U.S.A. (No.96)Sand Dollar, Sea Urchin, from Baja, California, U.S.A.
Pliocene Period, 7 Million Years Old

Measurements Approx.
Height - 1.4 cm
Width - 7.2 cm
Length - 7.5 cm



The Echinoids possess a rigid, globular skeleton made up of columns of thin, calcite plates (ambulacrals and interambulacrals). The plates known as ambulacrals have small pores for tube feet. All plates have swollen tubercles for the ball-and-socket articulation of spines, which are used for defence and some-times for walking. Regular Echinoids, which forage on the sea bed show radial symmetry; irregular Echinoids, which usually burrow in soft sea beds, show bilateral symmetry.
 

Share