title: [The tentacle apparatus of the red coral (Corallium rubrum L.) and its role in feeding behaviour].
abstract: The tentacles of the octocoral Corallium rubrum may become extremely elongated ("threadlike-tentacle") the apical part of the "norm-tentacle" becoming stretched more than three times as much as the base.The threadlike parts of the tentacles contract corcscrew-like when touched by food particles.The stimulated part of the tentacle is brought close to the mouth by coordinated movements of its basal portion. Very often both "threadlike-tentacle" and "norm-tentacle" shorten in order to carry the particle to the pharynx.When the "norm-tentacles" only are touched, they react with quick strokes towards the oral disc. This behaviour, when shown by all tentacles at the same time results in the formation of either a "tentacle-fist" or a basketlike structure. At slight irritations the "norm-tentacle" will respond with slow bending movements, which lead the particle towards the mouth. Independent of the type of tentacle reactions the prey is always checked before entering the pharynx, and very often refused.If the polyp decides to accept, food is transported quickly through the elongated pharynx and within a few minutes will have disappeared in the coelenteron.
authors.affiliation: II. Zoologisches Institut der Universität Wien, Wien, Österreich.
authors.forename: E F
authors.initials: EF
authors.lastname: Abel