Kaldane

The Kaldanes are a fictitious sapient species existing in the region of Bantoom on the planet Barsoom in the John Carter series of books by Edgar Rice Burroughs. Introduced in the book Chessmen of Mars, the Kaldanes are almost all head, but for six arachnoid legs and a pair of chelae. Their racial goal is to achieve pure intellect against bodily existence:

It is only your brain that makes you superior to the banth, but your brain is bound by the limitations of your body. Not so, ours. With us brain is everything. Ninety per centum of our volume is brain. We have only the simplest of vital organs and they are very small for they do not have to assist in the support of a complicated system of nerves, muscles, flesh and bone. We have no lungs, for we do not require air. Far below the levels to which we can take the rykors is a vast network of burrows where the real life of the kaldane is lived. There the air-breathing rykor would perish as you would perish. There we have stored vast quantities of food in hermetically sealed chambers. It will last forever. Far beneath the surface is water that will flow for countless ages after the surface water is exhausted. We are preparing for the time we know must come -- the time when the last vestige of the Barsoomian atmosphere is spent -- when the waters and food are gone. For this purpose were we created, that there might not perish from the planet Nature's divinest creation -- the perfect brain.

In order to function in the physical realm, the Kaldanes have bred the Rykors: a nonsentient complementary species composed of a body similar to that of a Red Martian but lacking a head; when the Kaldane places itself upon the shoulders of the Rykor, a bundle of tentacles connects with the Rykor's spinal cord, allowing the brain of the Kaldane to control its motor nerves and sensory nerves. Should the Rykor become damaged or die, the Kaldane climbs upon another.

Immediately I control every muscle of the rykor's body—it becomes my own, just as you direct the movement of the muscles of your body. I feel what the rykor would feel if he had a head and brain. If he is hurt, I would suffer if I remained connected with him, but the instant one of them is injured or becomes sick we desert it for another. As we could suffer the pains of their physical injuries, similarly do we enjoy the physical pleasures of the rykors.

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