"What do you notice about that?" he asked.

Caldwell stared obediently at the screen for a few seconds while Hunt watched in silence.

"It's a funny fish," Caldwell said at last. "Okay—you tell me."

"It is not obvious at first sight," Danchekker replied, "but by detailed comparison it is possible to relate the structure of that fish, bone for bone, to that of the Ganymean skeleton. They're both from the same evolutionary line."

"That fish is one of those that were found on the Lunarian base on Farside," Hunt said suddenly.

"Precisely, Dr. Hunt. The fish dates from some fifty thousand years ago, and the Ganymean skeleton from twenty-five million or so. It is evident from anatomical considerations that they are related and come from lines that branched apart from a common ancestral life form somewhere in the very remote past. It follows that they share a place of origin. We already know that the fish evolved in the oceans of Minerva; therefore, the Ganymeans also came from Minerva. We thus have proof of something that has been merely speculation for some time. All that was wrong with the earlier assumption was our failure to appreciate the gap in time between the presence of the Ganymeans on Minerva, and that of the Lunarians."

"Okay," Caldwell accepted. "The Ganymeans came from Minerva, but a lot earlier than we thought. What's the big message and why did you call us over here?"

"In itself, this conclusion is interesting but no more," Danchekker answered. "But it looks pale by comparison with what comes next. In fact"—he shot a glance at Hunt—"the rest tells us all we need to know to resolve the whole question once and for all."

The two regarded him intently.

The professor moistened his lips, then went on: "The Ganymean ship has been opened up fully, and we now have an extremely comprehensive inventory of practically everything it contained. The ship was constructed for large freight-carrying capacity and was loaded when it met with whatever fate befell it on Ganymede. The cargo that it was carrying, in my opinion, constitutes the most sensational discovery ever to be made in the history of paleontology and biology. You see, that ship was carrying, among other things, a large consignment of botanical and zoological specimens, some alive and in cages, the rest preserved in canisters. Presumably the stock was part of an ambitious scientific expedition or something of that nature, but that really doesn't matter for now. What does matter is that we now have in our possession a collection of animal and plant trophies the like of which has never before been seen by human eyes: a comprehensive cross section of many forms of life that existed on Earth around the late Oligocene and early Miocene periods, twenty-five million years ago!"

Hunt and Caldwell stared at him incredulously. Danchekker folded his arms and waited.