Molluscoidea

n. pl.
  1. A division of Invertebrata which includes the classes Brachiopoda and Bryozoa; -- called also Anthoid Mollusca.

Originally the Tunicata were included under Molluscoidea, from which they are known to differ widely in structure and embryology. Molluscoidea were formerly considered a subdivision of Mollusca, but they are now known to have more relationship with Annelida than with Mollusca.