hat he felt the thing's presence. He looked
up--and a strange sound came from him. For seconds he apparently could
not move, stark fear rooting him to the ground, the gun limp in his
hand.

Then a surge ran through the mound of flesh, and the arm, a pseudopod,
reached more rapidly for him.

It stung Quade into action. He leaped back, brought up his automatic,
and fired at the thing once; then three times more. He, and each one
of the others, saw four bullets thud into the heap of pallid matter
and heard them clang on the metal of the sphere beneath. They had gone
right through its flesh--but they showed no slightest effect!

Quade was evidently unwilling to leave the sphere. Jerking his arm up
he brought his trigger finger back again. A burst of three more shots
barked through the cavern, echoing and re-echoing. The man screamed an
inarticulate oath as he saw how useless his bullets were, and hurled
the empty gun at the monster--which was down on the floor now, and
bunching its sluggish body together.

The automatic went right into it. They could all see it there, in the
middle of the amorphous body, while the creature stopped, as if
determining whether or not it was food. Quade screwed his courage
together in the pause, and tried to dodge past to the door of the
sphere; but the monster was alert: another pseudopod sprang out from
its shapeless flesh, sending him back on his heels.

The feeler had all but touched Quade, and with the closeness of his
escape, the remnants of his courage gave. He yelled, and turned and
ran.

* * * * *

He ran straight for the three who watched from the tunnel mouth, and
the mound of shapeless jelly came fast on his trail. It came in
surging rolls, like thick fluid oozing forward; it would have been
hard to measure its size, for each moment it changed. The only
impression the four humans had was that of a wave of half-transparent
matter that one instant was a sticky ball of viscid flesh and the next
a rapidly advancing crescent whose horns reached far out on each flank
to cut off retreat.

By instinct Phil jerked Sue around and yelled at the professor to run,
for the old man seemed to be frozen into an attitude of fearful
interest. Bullets would not stop the thing--could anything? Holmes
wondered. He could visualize all too easily the death they would meet
if that shapeless, naked protoplasmic mass overtook and flowed over
them....

But he wasted