DEFINITION OF THE SAND DOLLAR
Sand dollars, like all members of the order Clypeasteroida, possess a rigid skeleton known as a test. The test consists of calcium carbonate plates arranged in a five fold radial pattern. In living individuals the test is covered by a skin of velvet-textured spines; these spines are in turn covered with very small hairs (cilia). Coordinated movements of the spines enable sand dollars to move across the seabed. The velvety spines of live sand dollars appear in a variety of colors—green, blue, violet, or purple—depending on the species. The tests of dead individuals are often found on beaches, the textured skin missing and the skeleton bleached white by sunlight.
The bodies of adult sand dollars, like those of other echinoids, display radial symmetry. The petal-like pattern in sand dollars consists of five paired rows of pores. The pores are perforations in the endoskeleton through which podia for gas exchange project from the body. The mouth of the sand dollar is located on the bottom of its body at the center of the petal-like pattern. Unlike other urchins, the bodies of sand dollars also display secondary front-to-back bilateral symmetry. The anus of sand dollars is located at the back rather than at the top as in most urchins, with many more bilateral features appearing in some species. These result from the adaptation of sand dollars, in the course of their evolution, from creatures that originally lived their lives on top of the seabed (epebenthos) to creatures that burrow beneath it (endobenthos). The common sand dollar, Echinarachnius parma, is widespread in ocean waters of the Northern Hemisphere, from the interdidal zone to considerable depths. It can be found in temperate and tropical zones. The keyhole sand dollar (three species, genus Mellita) is found on a wide range of coasts in and around the Caribbean Sea.
THE LEGEND OF THE SAND DOLLAR
OR
HOLY GHOST SHELL
is one of the most unusual specimens of marine life. The markings on the shell symbolize the Birth, Crucifixion and Resurrection of Christ. On the top side of the shell, an outline of the Easter Lily is clearly seen. At the center of the Lily a five pointed Star representing the Star of Bethlehem appears. The five narrow openings are representative of the four nail holes and the spear wound made in the body of Christ during the Crucifixion. Reversing the shell you will easily recognize the outline of the Christmas Poinsettia and also the bell. When broken, inside the shell are five little birds called the Doves of Peace. Some say they are the Angels that sang to the Shepherds the First Christmas Morning.
May Our Lord N Savior Jesus Christ Richly Bless You
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