The Oogenic Cycle of Nereis Diversicolor Under Natural Conditions

Abstract

Until recently, the most detailed and widely quoted account of the life cycle and reproductive biology of Nereis diversicolor O. F. Müller was that of Dales (1950; 1951) for a population in the Thames Estuary followed for a single season. The study combined a periodic analysis of the population structure with assessment of reproductive maturity, by gamete analysis of individual worms, and a record of larval recruitment. The conclusions reached were that worms grew to maturity in one year, spawning in February, but that some survived up to a maximum life span of 18 months.