Electron microscopical localization of chitin in the cuticle of Halicryptus spinulosus and Priapulus caudatus (Priapulida) using gold-labelled wheat germ agglutinin: phylogenetic implications for the evolution of the cuticle within the Nemathelminthes C. Lemburg ORIGINAL ARTICLE Pages: 137 - 158
Four lines of spermatid development and dimorphic spermatozoa in the sea urchin Anthocidaris crassispina (Echinodermata, Echinoida) D. W.-t. AuArkadiy Anatolievich ReunovRudolf Shiu-sun Wu ORIGINAL ARTICLE Pages: 159 - 168
Characteristics of spermiogenesis and mature spermatozoa in Gyratrix hermaphroditus (Plathelminthes, Rhabdocoela, Kalyptorhynchia) B. Sopott-EhlersUlrich Ehlers ORIGINAL ARTICLE Pages: 169 - 176
Ultrastructure of the nephrostome in Enchytraeus albidus (Annelida, Clitellata) Dieter Bunke ORIGINAL ARTICLE Pages: 177 - 182
Alterations of the eyes of Carinaria lamarcki (Gastropoda, Heteropoda) during the long pelagic cycle Michael J. F. Blumer ORIGINAL ARTICLE Pages: 183 - 194
