He stepped to the water, waded in. Lothar followed. "Hey!" yelled Rusty. "Why not build a raft? We can't swim that distance!" "Build a raft from what? Those trees won't float. And the water's only five feet at the deepest." Rusty gingerly waded in. The liquid, thicker than water but of similar elements, according to Spike, was covered with a thin film of vegetable oil. It was sticky, hot. Making slow progress in the heavy stuff, Rusty splashed along in the wake of the ponderous Lothar. The water slowly deepened to his chest. A scaly head popped up beside him. Water snake! Impulsively, Rusty struck out with his fist. The head disappeared, came to the surface again a short distance away. It was not a snake. It was a Venusian--_the_ Venusian. He looked at Rusty and scowled, if a _fish_ can scowl. Rusty stared, unbelieving. He had appeared so quietly the others had not turned. Where could he have come from? How could he have escaped the thing in the jungle? "How did you get here!" "Why do you strike at me, Earthman!" Rusty uselessly attempted to explain. They could never understand Earthian reactions. Rusty hated the green creatures. The Venusian sneered, swam silently to the others. "Well!" said Spike, with his usual calm. "We didn't expect to see you again! What happened?" "Tree _vwark_." "Oh," said Spike. He turned and waded on. Rusty stared, aghast. These men weren't human. "Hey!" he called. "What the hell's a 'Tree vwark?'" Spike turned and smiled. "_Vwark_ that lives in trees," he answered, turned back to the water. And Rusty knew he could expect nothing more. The Venusians were strange of body, had stranger ways. They never spoke of their activities. It was an instilled custom of their kind. And he knew why Spike had not interrogated further, uselessly. * * * * * Scattered and splashing, the four waded toward the distant hills. Earthmen, Venusian, Vulcanian. The Venusian swam easily ahead, often disappearing for long periods beneath the surface, absorbing oxygen from the water as adequately as from the air. Rusty, succumbing to his innate get-the-facts complex, asked if the seas contained life, was answered in the negative. But he questioned the statement when they passed a half-submerged creature that weighed well over five tons, heavy clawed limbs rearing stiffly. The air about it was a nausea. "Mud animal," explained Spike. "Life here came from the mire instead of the sea. With the exception of the Plain, the whole planet is covered with soft mud, thousands of miles deep. It is there that most of the life exists. This one probably got wounded, came blindly up and died." As the Earthian spoke, he halted, his face suddenly darkened. Rusty, advancing to him, felt a strong suction beneath his feet. Go back! But he could not turn back, nor go forward. "Lothar!" yelled Spike, but the mighty Vulcanian was also caught fast in the grim pull.