But that was impossible. Botanist or not, he knew the impossibility of it. It was all the more impossible on a remote islet where inbreeding must of necessity take place. The living forms might differ from those of other islands, but not from each other — at least, not in such incredible profusion. The number of species must be limited by the very intensity of competition on an island. Must be!

Carver stepped back a half dozen paces, surveying the forest wall. It was true. There were ferns innumerable; there were pines; there were deciduous trees — but there were, in the hundred yard stretch he could scan accurately, no two alike! No two, even, with enough similarity to be assigned to the same species, perhaps not even to the same genus.

He stood frozen in uncomprehending bewilderment. What was the meaning of it? What was the origin of this unnatural plenitude of species and genera? How could any one of the numberless forms reproduce unless there were somewhere others of its kind to fertilize it? It was true, of course, that blossoms on the same tree could cross-fertilize each other, but where, then, were the offspring? It is a fundamental aspect of nature that from acorns spring oaks, and from kauri cones spring kauri pines.

In utter perplexity, he turned along the beach, edging away from the wash of the waves into which he had almost backed. The solid wall of forest was immobile save where the sea breeze ruffled its leaves, but all that Carver saw was the unbelievable variety of those leaves. Nowhere — nowhere — was there a single tree that resembled any he had seen before.

There were compound leaves, and digitate, palmate, cordate, acuminate, bipinnate, and ensiform ones. There were specimens of every variety he could name, and even a zoologist can name a number if he has worked with a botanist like Halburton. But there were no specimens that looked as if they might be related, however distantly, to any one of the others. It was as if, on Austin Island, the walls between the genera had dissolved, and only the grand divisions remained.