The flying polyps (also called Elder Beings or Polypous Race) came to Earth out of space as conquerors about seven hundred fifty million years ago. They also inhabited three other planets in the solar system, including possibly Yaksh (Neptune) and Tond (though Tond itself may lie outside the solar system, or may be possibly referring to Pluto, which was discovered only 6 years before the publication of the story). On Earth, they built basalt cities with high windowless towers. When they attempted to colonize the oceans, the polyps were driven back by the Elder Things. Thereafter, they restricted their habitats to the surface world.