The man from Neptune lives on a world of great density, and he is forced to fight a grim environment. Tremendous gravity, an unstabloe surface, probably liquid with little land area, dense atmosphere, all present great problems.
Paul depicts the Neptunians like tailed amphibian reptiles with some batracian and lemurian features which have developed a primitive society, living in domed huts near bodies of water, whenever possible in underground areas.
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