Humanoid species. They developped a civilisation in the Small Magellanic Cloud, which they called Amambarane. Weak and stupid, they and were used by another species which settled on their homeworld before they discovered they had powerful telepathic abilities, and, after strengthening those power by selective breeding took, the reconquered their planet and then over the entire Amambarane. In the 13e and 20e millenaia, they tried to conquer the Milky Way but were repelled on every attempt.
Physically, they stand about the height as a kneeling adult human, and hide their bodies in robes when dealing with other species.Their body is glistening, moist looking with gray-green flesh which seems to writhe and flow as their limbs move with boneless fluidity. The head are small and spherically shaped. The face is blank with a small and somehow pretty mouth, two hole instead of a nose, and two big, filmed over, dull, obscurely opalescent eyes. They speak in sibilant whispers which change to a high whistling pitch when they are angry.
Intellectually, H'harn are quite intellectually inferior to most other space-faring species. They viewed all other sentient creatures as tools they can manipulate dominate with their power of mental compulsion. While this power is almost unmatched, it is limited in range, and cannot be used against many creatures at once. Its force can be used in such a way that the victim and those surrounding it are unaware of the control, but full possession makes the control obvious through the blank face of the victim.
Source: Return to the Stars (Edmund Hamilton)