or-o-don!"

The creature, walking erect and carrying a stick in one hand, advanced
at a slow, lumbering gait. It walked directly toward the gryfs who
moved aside, as though afraid. Tarzan watched intently. The Tor-o-don
was now quite close to one of the triceratops. It swung its head and
snapped at him viciously. Instantly the Tor-o-don sprang in and
commenced to belabor the huge beast across the face with his stick. To
the ape-man's amazement the gryf, that might have annihilated the
comparatively puny Tor-o-don instantly in any of a dozen ways, cringed
like a whipped cur.

"Whee-oo! Whee-oo!" shouted the Tor-o-don and the gryf came slowly
toward him. A whack on the median horn brought it to a stop. Then the
Tor-o-don walked around behind it, clambered up its tail and seated
himself astraddle of the huge back. "Whee-oo!" he shouted and prodded
the beast with a sharp point of his stick. The gryf commenced to move
off.

So rapt had Tarzan been in the scene below him that he had given no
thought to escape, for he realized that for him and Pan-at-lee time had
in these brief moments turned back countless ages to spread before
their eyes a page of the dim and distant past. They two had looked upon
the first man and his primitive beasts of burden.

And now the ridden gryf halted and looked up at them, bellowing. It was
sufficient. The creature had warned its master of their presence.
Instantly the Tor-o-don urged the beast close beneath the tree which
held them, at the same time leaping to his feet upon the horny back.
Tarzan saw the bestial face, the great fangs, the mighty muscles. From
the loins of such had sprung the human race--and only from such could
it have sprung, for only such as this might have survived the horrid
dangers of the age that was theirs.

The Tor-o-don beat upon his breast and growled horribly--hideous,
uncouth, beastly. Tarzan rose to his full height upon a swaying
branch--straight and beautiful as a demigod--unspoiled by the taint of
civilization--a perfect specimen of what the human race might have been
had the laws of man not interfered with the laws of nature.

The Present fitted an arrow to his bow and drew the shaft far back. The
Past basing its claims upon brute strength sought to reach the other
and drag him down; but the loosed arrow sank deep into the savage heart
and the Past sank back into the oblivion that had claimed his kind.

"Tarzan-jad-guru!" murmured Pan-at-lee, unknowingly