Tabla de Contenidos:
  • v. 1. Acoelomate and pseudocoelomate metazoans
  • v. 2. Entoprocts and lesser coelomates
  • v. 3. Annelids and echiurans
  • v. 4. Molluscs: Gastropods and cephalopods
  • v. 5. Molluscs: Pelecypods and lesser classes
  • v. 6. Echinoderms and Lophophorates
  • [v. 7-8 never published]
  • v. 9. General aspects: Seeking unity in diversity.