The invaders had apparently raided most of the surrounding country in obtaining those grafted half-heads. Near where Dixon stood there was a tragic little pile of articles taken from the Centaurians' victims--prospectors' picks, shovels, axes, and other tools. Over to the left of the dormant hybrids stood the second Alpha Centaurian, curiously examining Dixon's projectile. The creature apparently suspected the deadly nature of the gleaming cylinder for it soon laid it carefully down and packed cushions of soft fabric around it to shield it from any possible shock. Then at an unspoken command from the first Centaurian the great hybrid whirled Dixon around to face a small enclosure just behind him in which were located banks of control panels and other apparatus. One of the pieces of mechanism, with a regularly spaced stream of sparks snapping between two terminals, was apparently a radio receiver automatically recording the broadcast from the space ship. Dixon was unable to even guess the nature of the remaining apparatus. "Bruce, be careful!" Ruth called in despairing warning. "He is going to put the thought-reading machine on your brain. Then he'll learn what the projectile is for, and everything will be lost!" * * * * * Dixon's mind raced with lightning speed in the face of this new danger. He stealthily slipped a hand over the revolver in his pocket. There was one vulnerable spot in the great hybrid holding him, and that was the opalescent globe on the creature's head. If he could only smash that globe with one well-directed shot, he might be able to elude the Centaurians for the precious minute necessary to send the projectile on its deadly journey. The hybrid began maneuvering Dixon toward the instrument enclosure. For a fleeting second the grip of the tentacles upon his shoulders loosened slightly. Dixon took instant advantage of it. Twisting himself free from the loosened tentacle in one mighty effort, he whirled and fired pointblank at the opalescent globe on the head looming above him. The bullet smashed accurately home, shattering the globe like a bursting bubble. The great hybrid collapsed with startling suddenness, its life force instantly extinguished as the globe burst. Dixon leaped to one side and swung the gun into line with the Centaurian's hideous face. He pulled the trigger--but there was no response. The rusty old firearm had hopelessly jammed. Dixon savagely flung the revolver at the Centaurian. The creature tried to dodge, but the heavy gun struck its body a glancing blow. There was a slight spurt of body fluid as the chitinous armor was partly broken. Dixon's heart leaped exultantly. No wonder these creatures had to create hybrids to fight for them. Their own bodies were as vulnerable as that of a soft-shelled crab!