A great anthropoid male came rushing toward them. He had slipped back beyond speech, but ecstatic noises came out of his throat. Behind him were others, males, females, and young on the same evolutionary level. Winters and the silver she that was Jill were caught up and carried on in their tribal rush. Winters fought to get away, but it was hopeless. The wild hairy bodies walled him in. As they approached the center of the garden they were joined by more and more, all apparently summoned by the sound of the gong. Looking at them, Winters' stomach turned over. This was Walpurgis Night, a festival of blasphemies. And he was trapped in it, inextricably joined to destruction. The ones like Jill, who had only gone a little way as yet, were not so bad. They were human. Winters knew that he himself had been like that, and he felt no particular horror of them. But there were others. Back through all the stages of the primitive, beyond the Neanderthaler, beyond the Piltdown Man, beyond Pithecanthropus Erectus, beyond the missing Link, back to the common ancestor. Shapeless, shambling, hairy brutes, deformed skulls and little red cunning eyes, bared teeth grinning yellow. Things that even the anthropologists had never seen or dreamed of. Things that were not human, or ape, nor any form of life that had ever been classified. [Illustration: _All the dark secrets of Terran evolution were laid bare in this garden of evil, under that prism of hell!_] All the dark secrets of Terran evolution were laid bare in this garden, for the Martians to see. It made even Winters, the Earthman, flinch to think that bodies like that had given ultimate birth to him. What respect could the Martians have for such a race, that was still so close to its beginnings? But he was to see more, much more, of those beginnings.... * * * * * The gong struck a last booming summons. The tide of bowed hairy shoulders and flat brows and ugly things that went on all fours swept Winters and Jill out into the clearing at the center, where from the palace window he had seen the lake. A strong musky reek hung in the air. It had the same sickly taint that a snake-house does. And Winters saw that the lake was agitated by the creatures who lived there, and who were swarming out to answer the gong. _Back to the common ancestor, and beyond. Beyond the mammal, back to the gill and the scale, to the egg laid in the warm mud, to the hissing, squirming, utterly loathly ultimate!_ Jill panted, "Shanga! Shanga!", looking up, and Winters felt a darkness swimming in his brain. A cold wet thing slithered between his legs, and he swayed, retching. The surface of the lake rippled, but he would not look. He could not. Grasping Jill, he tried to batter his way through the crowd, but it was hopeless. He was caught, trapped. Looking up, he saw the prisms that were set high overhead on long booms. He saw them start to glow, with the remembered flame.