To me it is quite credible that the Martians may be descended from beings not unlike ourselves, by a gradual development of brain and hands (the latter giving rise to the two bunches of delicate tentacles at last) at the expense of the rest of the body. Without the body the brain would, of course, become a mere selfish intelligence, without any of the emotional substratum of the human being.

Book II, Ch. 2 (Ch. 19 in editions without Book division): What We Saw from the Ruined House - The War of the Worlds (1898)