The trunks (as he began to think of them) of the strange trees (though you could call them lampposts just as accurately) were rooted in the ground—where there had been pavement they had cracked and penetrated it—and Turk couldn't see far enough in any direction to really get his bearings. Everything faded, forty or fifty yards out, to a shimmering blue vagueness. To find the mall where the women and Isaac had last been seen they would have to navigate by compass and the clues directly under their feet.

"What do they live on?" Lise asked in a hushed voice. "There's no water here."

"Maybe more water than they're used to getting out where they usually grow," Turk said.

Dvali said, "Or they're using some catalytic process that doesn't need water, a completely different kind of metabolism. They must have evolved for billion of years in an environment far harsher than this."

A billion years of evolution. If that was true, Turk thought, then these things, as a species, if that word applied, were older than the human race itself.

* * * * *

They moved in silence through the Hypothetical forest, though it was not entirely a silent place. No wind reached them at street level, but there must have been a wind blowing, Turk guessed, because the iridescent globes that crowned the tubular trunks occasionally bumped against each other and made a gentle sound that suggested a rubber mallet on a wooden xylophone. And there was motion at ground level, too. Small blue tubes, like roots, periodically snaked between the trees, running with a whipcrack motion that might be quick and powerful enough to break a leg if you ran across one at the wrong time.

Twice Turk saw paperlike objects fluttering overhead, occasionally touching or merging with the globes—varieties of the thing that had attacked Isaac back in Bustee. Mistaking him for one of their own, Turk thought; or maybe it wasn't a mistake.

Lise walked close behind him. He could hear her indrawn breath every time something rattled or fluttered in the dim and shifting light. He felt bad about that, about the fear she was enduring and whatever else she might have to endure before they were finished here. He turned and said, "I'm sorry I got you into this."

She wouldn't let him finish. "Do you really think you're somehow responsible for what happened?"

"For taking you on this half-assed trip west, maybe."

"I made that choice."