"Over there." She pointed off toward the rim of the valley. "It goes down to the sea, I think. Long ago we used to go down there but there's no need, and the beasts make it dangerous."
"Do they," said Harker, and kissed her in the hollow below her chin. "What happens when the beasts come?"
Button laughed. Before he could stir Harker was trapped fast in a web of creepers and tough fern, and the black birds were screeching and clashing their sharp beaks in his face.
"That happens," Button said. She stroked the ferns. "Our cousins understand us, even better than the birds."
Harker lay sweating, even after he was free again. Finally he said, "Those creatures in the underground lake. Are they your cousins?"
Button's fear-thought thrust against his mind like hands pushing away. "No, don't.... Long, long ago the legend is that this valley was a huge lake, and the Swimmers lived in it. They were a different species from us, entirely. We came from the high gorges, where there are only barren cliffs now. This was long ago. As the lake receded, we grew more numerous and began to come down, and finally there was a battle and we drove the Swimmers over the falls into the black lake. They have tried and tried to get out, to get back to the light, but they can't. They send their thoughts through to us sometimes. They...." She broke off. "I don't want to talk about them any more."
"How would you fight them if they did get out?" asked Harker easily. "Just with the birds and the growing things?"
Button was slow in answering. Then she said, "I will show you one way." She laid her hand across his eyes. For a moment there was only darkness. Then a picture began to form—people, his own people, seen as reflections in a dim and distorted mirror but recognizable. They poured into the valley through a notch in the cliffs, and instantly every bush and tree and blade of grass was bent against them. They fought, slashing with their knives, making headway, but slowly. And then, across the plain, came a sort of fog, a thin drifting curtain of soft white.
It came closer, moving with force of its own, not heeding the wind. Harker saw that it was thistledown. Seeds, borne on silky wings. It settled over the people trapped in the brush. It was endless and unhurrying, covering them all with a fine fleece. They began to writhe and cry out with pain, with a terrible fear. They struggled, but they couldn't get away.
The white down dropped away from them. Their bodies were covered with countless tiny green shoots, sucking the chemicals from the living flesh and already beginning to grow.