Figure 23.32: Bilaterally Symmetrical Echinoderm Larvae become Radially Symmetrical Adults (A) The ciliated larva of a sea star has bilateral symmetry. Hemichordates have a similar larval form. (B) The radially symmetrical adult sea star displays the canals and tube feet of the echinoderm water vascular system, as well as the calcified internal skeleton. The body’s orientation is oral–aboral rather than anterior–posterior.