ter he shook his head dubiously. Too brazen, that
landing. It was almost in the insect city. Of course, the ship was
large and heavily armed with ray-guns which poked out their sharp
snouts here and there about the hull. None the less, an experienced
explorer of Titan would never have flung such defiance at the spiders.

The city was feverishly alive with the monsters now. They gathered in
groups to stare down at the strange craft, then raced away again,
darting in and out of their trap-door homes and streaking here and
there across the twisted, tortured granite of the mountainside. The
Queen's palace, a vast, raised cocoon of shimmering, silken web, was a
veritable bee-hive. Something was brewing!

Abruptly the trap-door homes vomited forth monstrous insects by the
thousands which spread with prodigious speed along the mountainside.
At an unseen signal they poured down upon the plateau and charged the
space-ship.

The black craft's heavy ray-guns broke into life. Attacking monsters
curled up and died as the rays bit into their onrushing ranks. The
first wave melted, but an instant later the following waves buried the
ship.

Insects in the rear darted here and there, dragging away dead and
dying spiders. Here was food aplenty! The denizens of the Trap-Door
City would live well on their dead for a few days.

Abruptly the attack ceased. The crackling ray-guns were still taking
toll as the monsters scurried back to the safety of their city,
leaving their dead piled high about the hull of the ship.

* * * * *

Penrun wondered if the monsters would abandon the heaps of their dead.
He rather expected that frenzied efforts would be made to retrieve
them for food. The problem was solved by those aboard the space-ship,
for presently it rose a score of feet in the air and moved a few
hundred yards nearer the waterfall that marked the headwaters of the
White River.

At once a frantic wave of spiders swept down across the plateau
scouring it clean of the dead monsters.

After that the Trap-Door City seemed deserted. Not a spider could be
seen near the shining, circular doors. Only here and there crouched a
huge, bristly warrior safe behind a jutting rock with his glittering
eight eyes fixed on the motionless black ship below.

Again the weary waiting. Penrun could only hope that it would not be
long before those aboard the black ship gave him some hint of where
the entrance to the Caves m