Abstract
Polyps of the White Sea hydroid Sarsia producta were collected, described and figured, in order to gain new insight into its ecology, morphology, colonial structure, and behaviour. Specific modes offeeding behaviour were observed on hydro ids in situ, and their diet was examined. The diet of Sarsia producta is diverse and based on a wide range of items from different systems: dead organic matter, settled on the substrate or suspended in the water, phytoplankton and zooplankton, and epibenthic animals and algae. Successful capture of such a variety of food items is achieved by the particular feeding movements of the flexible body, well co-ordinated with the movements of hypos tome and capitate tentacles. In total, these movements create a complicated feeding behaviour unusual among hydroids.