The attractive factor in the settlement of Ophelia bicornis Savigny

Abstract

Largely as a result of experiments made in 1951, sands were classed as attractive, neutral or repellent (Wilson, 1953 a); but only after the 1952 experiments had been completed did it become reasonably certain that the sands in which the larvae of Ophelia bicornis Savigny readily settle carry an attractive factor apparently distinct from a repellent one present in sands in which they will not settle (Wilson, 1953 b). Whilst the precise natures of the factors were uncertain, it seemed probable that they both derive from organic activity. The 1953 breeding season was devoted to an attempt to obtain more information about the attractive factor.