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The fascination of the Annelida to scientists lies in the beauty of their structures and the functionality of their body plan, the tremendous adaptive radiation which has made it possible for these animals to colonize almost all marine, limnic and terrestrial biotopes. In doing so they have evolved a great variety of life forms, and their reproduction and development are correspondingly diverse, with many modes and patterns unique in the animal kingdom. In this special volume recent progress in this broad research area is presented by 26 specialists, in general through surveys or treatments of selected examples. Some of them review important annelid taxa such as the Nereididae, Syllidae, Spionidae, Cirratulidae, Clitellata, and Pogonophora; others analyse reproductive and developmental structures and phenomena in annelids, e.g. segmental organs, sex pheromones, oogenesis, mating systems, sperm types, life cycles, larval settlement, cleavage and symmetry of embryos, or discuss controversial approaches to annelid systematics. The book will be of interest to all zoologists who work with annelids as well as to embryologists and other researchers in reproductive biology.

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Preface. List of participants. Reproductive and developmental phenomena in annelids: a source of exemplary research problems; A.E. Fischer. Structure, function and development of segmental organs in Annelida; T. Bartolomaeus. Reproduction of the Syllidae (Annelida: Polychaeta); H.-D. Franke. Reproduction and larval development of the spioniform Polychaeta with application to systematics and phylogeny; J.A. Blake, P.L. Arnofsky. Reproduction and development in Cirratulidae (Annelida: Polychaeta); M.E. Petersen. Divergence of reproductive and developmental characteristics in Hediste (Polychaeta: Nereididae); M. Sato. Nereidid polychaetes as model organisms for marine chemical ecology; J.D. Hardege. Metabolite supply in oocytes of Nereis virens: role of nucleosides; U. Hoeger, et al. Polychaete aquaculture and polychaete science: a mutual synergism; P.J.W. Olive. Development of Perviata and Vestimentifera (Pogonophora); E.C. Southward. Sexual conflict and mating systems in the dorvilleid Ophryotrocha and the dinophilid Dinophilus; G. Sella, L. Ramella. Polychaete sperm: Phylogenetic and functional considerations; G.W. Rouse. Sperm types and their use for a phylogenetic analysis of aquatic clitellates; M. Ferraguti, C. Erséus. Larval settlement of polychaetes; P.-Y. Qian. Conservation and innovation in spiralian development; J.J. Henry, M.Q. Martindale. The ancestral cleavage pattern of the clitellates and its phylogenetic deviations; W. Dohle. Cellular origins of bilateral symmetry in glossiphoniid leech embryos; D.A. Weisblat. Systematization of the Annelida: different approaches; W. Westheide, et al. Index.

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Wilfried Westheide, geb. 1937 in Bielefeld. Studium der Biologie/Chemie und Geographie in Göttingen und Freiburg. 1988 Berufung auf einen Lehrstuhl für Spezielle Zoologie an der Universität Osnabrück.
Forschungsschwerpunkte: Morphologie, Systematik und Evolution Wirbelloser Tiere, insbesondere der Anneliden.

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