The declining sun lighted brilliantly the eastern banks of Korus, the crimson sward, the gorgeous forest. Beneath the trees we saw feeding many herds of plant men. The adults stood aloft upon their toes and their mighty tails, their talons pruning every available leaf and twig. It was then that I understood the careful trimming of the trees which had led me to form the mistaken idea when first I opened my eyes upon the grove that it was the playground of a civilized people.
As we watched, our eyes wandered to the rolling Iss, which issued from the base of the cliffs beneath us. Presently there emerged from the mountain a canoe laden with lost souls from the outer world. There were a dozen of them. All were of the highly civilized and cultured race of red men who are dominant on Mars.
The eyes of the herald upon the balcony beneath us fell upon the doomed party as soon as did ours. He raised his head and leaning far out over the low rail that rimmed his dizzy perch, voiced the shrill, weird wail that called the demons of this hellish place to the attack.
For an instant the brutes stood with stiffly erected ears, then they poured from the grove toward the river's bank, covering the distance with great, ungainly leaps.
The party had landed and was standing on the sward as the awful horde came in sight. There was a brief and futile effort of defence. Then silence as the huge, repulsive shapes covered the bodies of their victims and scores of sucking mouths fastened themselves to the flesh of their prey.
I turned away in disgust.
"Their part is soon over," said Thuvia. "The great white apes get the flesh when the plant men have drained the arteries. Look, they are coming now."
As I turned my eyes in the direction the girl indicated, I saw a dozen of the great white monsters running across the valley toward the river bank. Then the sun went down and darkness that could almost be felt engulfed us.
Thuvia lost no time in leading us toward the corridor which winds back and forth up through the cliffs toward the surface thousands of feet above the level on which we had been.
Twice great banths, wandering loose through the galleries, blocked our progress, but in each instance Thuvia spoke a low word of command and the snarling beasts slunk sullenly away.