Abstract
Two new deep-living species of the genus Bargmannia (Siphonophorae, Physonectae, Pyrostephidae) are described based, almost exclusively, on the nectophores of single specimens collected by ROVs off the west coast of California. The nectophores of B. stenotes sp. nov. were relatively small, up to 11.4 mm in length and, in the preserved condition had very narrow nectosacs. There was a marked bend in the distal part of the preserved nectophore, resulting in the ostium opening upwards. The mature nectophores of B. profunda sp. nov. were almost twice as long as those of B. stenotes and were characterised by the fact that the lower lateral ridges did not join, distally, with the meso-lateral ones. This feature also was present in smaller nectophores of B. amoena but those of B. stenotes, at that stage, did not have a mouth-plate.
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