We had a lovely tour of Sarasota Bay on the Carefree Learner. The first question of the day was, "What's this?" Look closely at the different pieces and see if you can figure it out.
. (Double-click on the image if you want a closer view.)
. (Double-click on the image if you want a closer view.)
Our best answer is that it is the TEST of a sand dollar or sea urchin, possibly an inflated sea biscuit. Both are in the class Echinoidea. `Sand dollars would have a felt-like coating of fine brown moveable spines.
Sea urchins are covered with tubular spines.
SEA BISQUIT (top above, bottom view below)