nd Tom lay flat on the ground and trained their rifles on the
approaching beast.

"I'll take the right leg," said Roger. "You take the left, Tom."

"On target!" replied Tom, squinting through the sight.

"Ready!" Connel's voice roared across the trail.

Only a hundred and fifty feet away the tyrannosaurus, hearing Connel's
voice, suddenly stopped. Its head weaved back and forth as though it
suspected a trap.

"Fire!" roared Connel.

Tom and Roger fired together, but at the same moment the monster lunged
toward Connel's position. Both shots missed, the energy charges merely
scorching its sides.

[Illustration]

The tyrannosaurus roared with anger and turned toward the boys, head
down and the claws of its short forelegs extended.

At that moment Connel opened fire, aiming for the monster's vulnerable
neck. But it was well protected behind its shoulders and the spaceman
only succeeded in drawing the beast's attention back to himself.

At this instant Tom and Roger opened fire again, sending violent shock
charges into the beast's hide. Caught in the withering cross fire, it
turned blindly on the boys and charged at them. The two cadets fired
coolly, rapidly, unable to miss the great bulk. The air became acrid
with the sharp odor of ionized air. Maddened now beyond the limits of
its endurance, hit at least twenty times and wild with pain, the great
king of the Venusian jungle bore down on the two cadets.

[Illustration]

Roger and Tom saw that their fire was not going to stop the
tyrannosaurus's charge. They were pouring a nearly steady stream of fire
into the monster now, while on the other side of the trail Connel was
doing the same, raking the monstrous hulk from the forelegs to the
hindquarters.

The boys jumped back, Tom still facing the beast and firing his rifle
from the waist. But Roger stumbled in the tangle of the underbrush and
fell backward, dropping his rifle. The beast's head swooped low, jaws
open.

Seeing Roger's danger, Tom jumped downward again without hesitation and
fired point-blank at the beast's scaly head, only ten feet away.

The monster roared in sudden agony and pulled back, jerking his head up
against a thick branch of the tree overhead. The limb tore loose under
the impact and fell crashing to the ground on top of Roger.

From behind, Connel stepped closer to the tyrannosaurus and fired from a
twenty-five-foot range. It wavered and stumbled back, obviously mortally
wounded. Fr