Marable had run to the other side of the ma.s.s. The air, rushing in from the windows, had cleared the mist, in spite of the new clouds the creature had emitted, and Betty could see for some feet in either direction now.

She walked, with stiff, frozen muscles, around to join Marable. As she came near to him, she saw him jerking off the entire canvas cover of the block to expose the horrible reptile to the light of day.

And now the two stood staring at the awful sight. The creature had flattened itself into the crevices and irregular surfaces of the block, but it was too large to hide in anything but a huge s.p.a.ce. They saw before them its great bulk, bright red skin blotched with black, which rose and fell with the breathing of the reptile. Its long, powerful tail, tapering off from the fat, loathsome body, was curled around the bottom of the block.

"That's where it's been hidden, under the shroud. We've been within a few feet of it every moment we've been at work," said Marable, his voice dry. "There were many hiding places for it, but it chose the best. It came out only when there was comparative quiet, to get its food...."

"We--we must kill it," stammered the girl.

But she could not move. She was looking at the immense, cruel, lidless eyes, which balefully held her as a serpent paralyzes a bird. The tubular nostrils and antennae seemed to be sniffing at them, waving to and fro.

"See the white expanse of cornea, how large it is," whispered Marable.

"The pupils are nothing but black slits now." The interest excited by this living fossil was almost enough to stifle the dread of the creature in the man.

But the girl saw the huge flat head and the crinkled tissue of the frilled mouth with its sucker disks.

Suddenly, from the central portion of the sucker-cup mouth issued a long, straight red fang.

The two drew back as the living fossil raised a short clawed leg.

"It has the thick body of an immense python and the clawed legs of a dinosaur," said Marable, speaking as though he were delivering a lecture. The sight, without doubt, fascinated him as a scientist. He almost forgot the danger.

"Oh, it's horrible," whispered the girl.

She clung to his arm. He went on talking. "It is some sort of terrestrial octopus...."

To the girl, it seemed that the living fossil was endless in length.

Coil after coil showed as the ripples pa.s.sed along its body and the straight fang threatened them with destruction.

"See, it is armored," said Marable.

"Betty, no one has ever had such an experience as this, seen such a sight, and lived to tell of it. It must be ravenous with hunger, shut up in its amber cell inside the black fluid. I--"

A sharp, whistling hiss interrupted his speech. The reptile was puffing and swelling, and as it grew in bulk with the intake of the air, its enamel-like scales stood out like bosses on the great body. It spat forth a cloud of black, oily mist, and Marable came to himself at last.

He raised his revolver and fired at the creature, sending shot after shot from the heavy revolver into the head.

Betty Young screamed as the reptile reared up and made a movement toward them. Marable and the girl retreated swiftly, as the beast thumped to the floor with a thud and started at them, advancing with a queer, crawling movement.

It was between them and the door. Betty thrust her gun into Marable's hands, for his own was empty and he had hurled it at the monster.

"Hurry! Run for your life!" ordered Marable, placing himself between Betty and the reptile.

She would not leave him till he swerved to one side, going dangerously close to the beast and firing into its head. The rush of the flowing body stopped; it turned and pursued him, leaving the girl safe for the moment, but separated from Marable.

Luckily, on the smooth marble it could not get an efficient grip with its clawlike arms. It was clumsy in its gait, and for a time the man eluded it.

Betty Young, looking about for a weapon, calling for help at the top of her lungs, caught sight of a fireman's ax in a gla.s.s case on the wall.

She ran over, smashed the gla.s.s with the small hammer, and took out the heavy ax.

Shot after shot reverberated through the big laboratory as Marable tried to stop the monster. Betty, bravely closing in from the rear, saw Marable leaping from side to side as the brute struck viciously at him time and again.

The creature had been emitting cloud after cloud of black fog, and the atmosphere, in spite of the open windows, was dim in its vicinity.

Vaguely Betty heard shouts from the far hall, but all she could do was to call out in return and run toward the horror.

Marable, out of breath, had climbed to the top of an amber block. Betty, close by, saw the reptile rear its bulk up into the air, until it was high enough to strike the man.

Before it could send forth its death-dealing fang to pin Marable to the block, however, Betty Young brought the ax down on its back with all her strength.

There was a sickening thud as the sharp weapon sunk deep into the fleshy back. She struck again, and the creature fell in folds, like a collapsing spring. It lashed back at her, but she leaped clear as it slashed in agony, thrashing about so that the whole room seemed to rock.

Marable came scrambling down the side of the block to help her. He was breathing hard, and she turned toward him; as Betty looked away, a portion of the scarlet tail hit her in the body and she fell, striking her head on the floor.

Marable reached down, seized the ax, and in a desperate frenzy hacked at the reptile's awful head. He leaped in and out like a terrier, sinking the ax deep into the neck and head of the beast. He gave the impression of slashing at heavy rubber, and Betty Young, trying to drag herself away from that dangerous body, heard his whistling breath.

They were almost hidden from one another now, in the mist which came from the thing's nostrils.

"Help, help!" screamed the girl, mustering her last strength in the despairing cry.

She saw Marable go down, then, as the reptile hit him a glancing blow with its body. When the powerful young fellow did not rise, the girl thought it was all over. The air really became black to her; she fainted and lay still.

When Betty Young opened her eyes, the air had cleared greatly, and she could see the familiar outlines of the paleontological laboratory and the bulks of the amber blocks. Her father was holding her head in his lap, and was bathing her temples with water.

"Darling," he said, "are you badly hurt?"

"No," she murmured faintly. "I'm--I'm all right. But--but Walter--did it--"

"He's all right," said her father. "The reptile was dying, and could do him no damage. We finished it off."

Then, Marable, covered with blood, which he was trying to wipe from his hands and clothes, came and smiled down at her.

"Well," said Professor Young, "you two have mutilated a marvelous and unique specimen between you."

There were several men examining something nearby. Turning her eyes in their direction, Betty saw they were viewing the remains of the reptile.

Marable helped her to her feet, and stood with one arm about her.

Professor Orling, the famous specialist on fossil reptiles, was speaking now, and the others listened.