Hydroids from submarine cliffs near Arthur Harbour, Palmer Archipelago, Antarctica

At the instigation of Dr. Joel W. Hedgpeth, Resident Director, Marine Science Center, Oregon State University, Newport, Oregon, U.S.A., I studied samples of hydroids, collected by Dr. John C. McCain and Dr. William E. Stout from submarine cliffs in the region around Palmer Station, Antarctica. The hydroids had been obtained during an examination of the zonation of rocky substrates in that area in the austral summer of 1968-1969. During this survey 0.25 m2 samples were scraped from the rocks at 5 feet intervals down to a depth of 50 feet and at 10 feet intervals from 50 to 100 feet. Dr. McCain and Dr. Stout were able to complete one such transect and a portion of another (Hedgpeth, in litt., see also McCain & Stout, 1969). The bulk of the material on which the present notes are based, is now in the collection of the Rijksmuseum van Natuurlijke Historie, Leiden, Netherlands; duplicates have been deposited in the U.S. National Museum (Smithsonian Institution), Washington, U.S.A. I want to express my gratitude to Dr. Joel W. Hedgpeth and Dr. John C. McCain for placing the interesting material at my disposal. The positions of the two stations from which material has been studied are Sta. 4, 64o 46' 36" S, 64o 03' 29" W, and Sta. 5, 64o 49' S, 64o 08' W; both are in the vicinity of Arthur Harbour, Palmer Archipelago, Antarctica. From each station there are several samples, taken at varying depths (in feet, suffixed with station number). Sta. 4-15 (about 5 m depth, 25.i.1969): Unidentifiable hydroid, probably athecate Eudendrium antarcticum Totton, one fragment; Symplectoscyphus glacialis (Jäderholm), fragment of 4 mm length. Sta. 4-20 (about 6 m depth, 25.i.1969):