Published by the American Geophysical Union as part of the Antarctic Research Series, Volume 26.

Species in the genera Hyarachna, Echinozone, Pseudarachna, and Aspidarachna, all in the family Hyarachnidae, are reviewed and critically discussed. A key to genera is presented along with a table of the species in each genus from antarctic waters. The genus Echinozone is redefined on new specimens from Anvers Island. A summary of each species in Echinozone is included, and the genus is redefined. Pseudarachna is briefly discussed, and a second species is added to the genus. In the family Janiridae, Notasellus and Austrofilius are brought out of synonymy on the basis of specimens from Anvers Island, and the species of Iathrippa and Neojaera are discussed with a critical review of each species. The genera Nostasellus and Austrofilius are redefined. Ectias is redefined on specimens of the type species from Anvers Island, and a species from South Africa is added to the genus. Maps of the distribution of many of the species are included.