marks a paleontologist anywhere in the universe.

At this time he had cut perhaps a foot into the tuff for the full three-foot width of the crack and from terrace level up to about his own height. In spite of its apparently firm texture, the rock was extremely soft; and the old question about erosion was reappearing. Big pockets of extremely crumbly material had been responsible for most of his speed. Now, however, with the usual perversity of the inanimate, a firmer substance was encountered, apparently encasing the bones he suspected of existing a little farther on. This combined with his increased care to bring almost to a halt the removal of rock from the cleft.

The bones were there. Perhaps they had been betrayed by a discoloration of the rock too faint for him to have noticed consciously; perhaps something more subtle is involved in the makeup of a successful field worker in paleontology, but as flake after flake of the matrix fell away under his attack a shape gradually took form.

At first a single bone which might have been an unusually short digit or an unusually long carpal—or, of course, something totally unrelated to either—was outlined. Then another, close enough to suggest that their lifetime relationship might have been maintained. And another—Sulewayo failed to hear the approach of the helicopter until its rotor wash from a hundred feet above lifted the dust about his ankles.

Knowing that Lampert would be having trouble holding that close to the cliffside, the paleontologist reluctantly hooked his equipment to his belt and started up the ladder. Five minutes later they were back in the camp, with Krendall listening eagerly to Sulewayo's description of his find.

"It's certainly a vertebrate, Hans. That stuff can't possibly be shell or wood. It's almost certainly a land dweller—"

"Likely enough in that sort of rock, anyway."

"—because I got enough uncovered to be nearly certain that it's a foot. Certainly a limb that would not be needed by a swimmer."

"Like an ichthyosaur?" queried Lampert innocently. Sulewayo grinned.

"Quite possibly. More likely one of our ubiquitous amphibids, though. Certainly something worth getting out, since the general idea is to get an evolutionary sequence of some sort."

"I suppose that means you'll want me to date the eruption which filled all these 

 Prev. P 28/59 next