posed, and that in all probability it connected at its southern extremity with the rise between Bouvet Island and the South Orkneys and South Georgia. This extension of the Mid-Atlantic Rise is now known as the "Scotia Rise."
These investigations tend to show a separation between the "deeps" ("deeps" are those parts of the oceans which are deeper than 3,000 fathoms) discovered by the Valdivia lying to the south-east of Bouvet Island, which may be suitably known as the "Ross Deep," and the deep lying to the south-west of South Africa, as well as that deep lying to the north of South Georgia and to the east of Argentina; all these "deeps" are separated from one another by "rises" of less than 2,000 fathoms.
The work of the Challenger, Valdivia, Gauss and Scotia in the South Atlantic and South Indian Oceans has given us a clue to the possible connections between Africa, South America and Antarctica, and now it is of great interest and importance to get more soundings to the south of Australia and New Zealand, to show more exactly what the conformation of the floor of the ocean is in those longitudes. That is one of the most important investigations for future Antarctic exploring ships to carry out.
The bathymetry of the Arctic Ocean is simple compared with that of the Antarctic Ocean, and consists of a basin almost completely sur-
