Do the Naticidæ Drill by Mechanical or by Chemical Means?

Abstract

The ability of marine prosobranchs (Nucella, Ocinebra, Natica) to drill holes in the shells of other mollusca, afterwards introducing their proboscis to suck out the soft parts of their victims, has been known by man during the past two thousand or so years¹. Nevertheless, it has still not been decided whether this drilling takes place by mechanical means only or whether a secretion of acid from the pharynx, the salivary glands or (in the Naticidæ) from the so-called boring gland takes part in the process. Schiemenz², Hirsch³, Boettger⁴, and Ankel^5,6 are all of opinion that secretion is active during drilling, whereas Fischer⁷ and Pelseneer⁸ feel convinced that drilling is carried out with the radula, that is, by mechanical means only.