already mentioned is a good geological example in illustration of the displacement theory (Fig. 14). At least a limited interchange of forms still took place in the Pliocene between Tierra del Fuego and Graham Land, which was only possible if both promontories still lay in the neighbourhood of the crescent-shaped curve of the South Sandwich Islands.
_-_figure_14.jpg)
Fig. 14.—Depth chart of the Drake Straits, after Groll.
Since then they have drifted westwards, but their narrow connection remains stuck fast in the sima. The manner in which the echeloned successive chains were stripped off one after another from the advancing blocks and were left behind is distinctly seen in the depth chart.[1] The group of the South Sandwich Islands, lying directly in the middle at the place of
- ↑ The best chart of the Drake Straits is that drawn by H. Heyde, which is reproduced by F. Kühn (see page 72). The deviations of our figure from it are unimportant.
