01-10-2008, 12:07 PM
This appears to be a piece of a sea urchin shell. The shell or "test" is made up of individual small plates which often separate after the death of the animal. Each plate has a raised protuberance which is the "ball" of a ball and socket joint by which the spines are attached to the shell. Something like this:
<a href="http://www1.istockphoto.com/file_thumbview_approve/716931/2/istockphoto_716931_sea_urchin_skeleton_2.jpg" target="_blank"><!-- m --><a class="postlink" href="http://www1.istockphoto.com/file_thumbview_approve/716931/2/istockphoto_716931_sea_urchin_skeleton_2.jpg">http://www1.istockphoto.com/file_thumbv ... eton_2.jpg</a><!-- m --></a>
<a href="http://upload.wikimedia.org/wikipedia/commons/thumb/7/77/Sea_urchin_tests.jpg/180px-Sea_urchin_tests.jpg" target="_blank"><!-- m --><a class="postlink" href="http://upload.wikimedia.org/wikipedia/commons/thumb/7/77/Sea_urchin_tests.jpg/180px-Sea_urchin_tests.jpg">http://upload.wikimedia.org/wikipedia/c ... _tests.jpg</a><!-- m --></a> Â <span class="petit">--Last edited by paul monfils on 2008-01-10 15:10:21 --</span>
<a href="http://www1.istockphoto.com/file_thumbview_approve/716931/2/istockphoto_716931_sea_urchin_skeleton_2.jpg" target="_blank"><!-- m --><a class="postlink" href="http://www1.istockphoto.com/file_thumbview_approve/716931/2/istockphoto_716931_sea_urchin_skeleton_2.jpg">http://www1.istockphoto.com/file_thumbv ... eton_2.jpg</a><!-- m --></a>
<a href="http://upload.wikimedia.org/wikipedia/commons/thumb/7/77/Sea_urchin_tests.jpg/180px-Sea_urchin_tests.jpg" target="_blank"><!-- m --><a class="postlink" href="http://upload.wikimedia.org/wikipedia/commons/thumb/7/77/Sea_urchin_tests.jpg/180px-Sea_urchin_tests.jpg">http://upload.wikimedia.org/wikipedia/c ... _tests.jpg</a><!-- m --></a> Â <span class="petit">--Last edited by paul monfils on 2008-01-10 15:10:21 --</span>