The genus Bouillonia (Cnidaria: Hydrozoa: Anthoathecata). Three species from the northern and southern hemispheres, with a discussion of bipolar distribution of this genus

Representatives of three species of Bouillonia Petersen, 1990 are studied and described: syntype specimens of Bouillonia cornucopia Bonnevie (1898), from the Zoological Museum, University of Oslo; a putative new species from the Arctic (“Polarstern”, 1995); and Bouillonia denhartogi spec. nov. from the Antarctic: Weddell Sea (“Polarstern”, 2000, 2005), Antarctic Peninsula (“Lawrence M. Gould”, 2002, 2003), S. Sandwich Is. (“Nathaniel B. Palmer”, 2004), and the Ross Sea, (“Nathaniel B. Palmer”, 2005). Characters given by Petersen for the genus are discussed and a new, wider description of Bouillonia is proposed. Questions concerning the bipolar distribution of this genus are also discussed.