Animals that possess two pairs of symmetrical sides are said to be biradially symmetrical. Biradial symmetry is a combination of radial and bilateral symmetry as seen in ctenophores. There are only two planes of symmetry, one through the longitudinal and sagittal axis and the other through the longitudinal and transverse axis. eg. Comb jellyfish – Pleurobrachia.
Animals that have two similar halves on either side of the central plane show bilateral symmetry. It is an advantageous type of symmetry in triploblastic animals, which helps in seeking food, locating mates and escaping from predators more efficiently. Animals that . have dorsal and ventral sides, anterior and posterior ends, right and left sides are bilaterally symmetrical.
