Crinoids, sometimes called sea lilies, have three major parts. The stem is segme…
Crinoids, sometimes called sea lilies, have three major parts. The stem is segmented and attaches to the bottom, the body or calyx (partial imprint shown here) contains the organs, and arms that gather food. Some varieties have survived the mass extinctions, but are not as plentiful as they were when this one was alive, about 330 million years ago. These fossils are common in the limestones of central USA and other areas.
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