ON THE GEOGRAPHICAL DISTRIBUTION OF RECENT NAUTILUS
现生鹦鹉螺类的地理分布

The present study deals with the geographical distribution of living Nautilus and drift shells, the relationship between marine environmental factors and distribution and that between behavior and distribution. These results may be summarized as follows: 1. The pressure of sea water is probably the most important factor of the distribution limitation of living Nautilus. The Reed Bank and Palawan Trough, both are over 2,000 meters in depth, possibly constitute two great barriers that prevent the living Nautilus pompilius from distributing to the west of Philippine Islands. 2. The oceanic currents would be the most effective agency to move the drift shells of Nautilus. The distribution line of the drift shells of Nautilus pompilius from the east coast of Taiwan Province to the southern Japanese Islands of Pacific coast coincides with that of the current direction of Kuroshio.