The planet of the Devidians, aliens who traveled through time to feed on the neural energy of dying humans.
Devidia II is the world of the Devidians, beings who exist slightly out of phase with normal time. They used a cave on the planet as a gateway to travel to Earth's past.
In Time's Arrow and Time's Arrow Part II, the Enterprise traces evidence of the Devidians to Devidia II, where a time portal sends Data and later other crew members to 1893 San Francisco. Once Picard is back aboard, the Enterprise fires time-phased photon torpedoes that destroy the Devidian habitat.