- Oncidium tonganum, a littoral Pulmonate, found on the shores of the Indian and Pacific Oceans (Mauritius, Japan).
Although the species are fewer in number than in most other families of fishes, they are widely spread and extremely abundant, peopling by countless schools the oceans of the tropical and temperate zones, and approaching the coasts only accidentally, occasionally, or periodically.
This deviation is the adoption of an aquatic mode of life by the European fresh-water spider (Argyroneta) and by the marine spider Desis, which is found on the shores of the Indian and Pacific Oceans from Cape Colony to eastern Australia.
Penck proposed to prepare a map of the world, including the oceans, on a scale of 1: 1,000,000, and his scheme was promised the support of a committee which met in London in 1909, and upon which were represented the leading powers of the world.
A bathymetrical chart of the oceans, by Professor J.