The genus Sclerostyla is better known from fossil records than from recent material (WRIGLEY, 1951; MÜLLER, 1970). This is not surprising, since Sclerostyla ctenactis is difficult to find, the tube usually being imbedded in the substrate. Such material was studied only by MÖRCH (1863) in the Zoologiske Museum, København; by AUGENER (1922) in the zoological museums of Berlin and Hamburg; by TREADWELL (1929) in the American Museum of Natural History and by WRIGLEY (1951) in the Allan Hancock Foundation, Los Angeles. The specimens have been reexamined. Additional specimens were collected by Dr. P. WAGENAAR HUMMELINCK (1955, 1963—64) and by the author (1970). This material, as a rule, was preserved with formaldehyde and, after a short period, transferred to alcohol. These specimens are deposited mainly in the Rijksmuseum van Natuurlijke Historie, Leiden (Nrs. 04466— 04476) or in the author’s collection (tHU 119, and tHU 121—127). Single specimens have been presented to the Zoologisches Museum, Berlin, D.D.R. (ZMB), to the Zoologisches Museum, Hamburg (ZMH), to the Zoologiske Museum, København (ZMK), to the British Museum Natural History, London (BMNH ZB. 1971. 228— 231), to the Allan Hancock Foundation, Los Angeles (AHF), to the Station Marine d’Endoume, Marseille (SME), to the American Museum of Natural History, New York (AMNH) and to the National Museum of Natural History, Washington (USNM).