Echiuroidea sentence example
- There appears to be little either in the development or in the structure of the Haplodrili to warrant the view held by Hatschek and Fraipont that Polygordius and Protodrilus are exceedingly primitive forms, ancestral to the whole group of seta-bearing Annelids (Oligochaeta, Polychaeta, Hirudinea and Echiuroidea).
- They are divided as follows: (i) Haplodrili or Archiannelida; (2) Chaetopoda; (3) Myzostomida, probably degenerate Polychaeta; (4) Hirudinea (see CHAETOPODA and LEECH); (5) Echiuroidea.
- There is a definite Annelid group (see Annelida), including the Archiannelida, the bristleworms (see Chaetopoda), of which the earthworm (q.v.) is the most familiar type, the Myzostomida, Hirudinea (see Leech) and the armed Gephyreans (see Echiuroidea).