Brachiopods have been at various times placed with the Mollusca, the Chaetopoda, the Chaetognatha, the Phoronidea, the Polyzoa, the Hemichordata, and the Urochordata.
Classes: Crustacea, Arachnida,Myriapoda,Insecta,Chaetognatha, Annelida.
CHAETOGNATHA, the name given by R.
Chaetognatha are hermaphrodite.
The conception of the Dipleurula derives its chief weight from the fact that it is comparable to the early larval forms of other primitive coelomate animals, such as Balanoglossus, Phoronis, Chaetognatha, Brachiopoda and Bryozoa.
The Phoronidea (q.v.) are now associated with Hemichordata (q.v.) in the line of vertebrate ancestry, whilst the Chaetognatha (q.v.) remain in solitary isolation.