"I saw him," Baba clicked excitedly. "He was big. I'm sure if we could catch him he'd be a friend! I tried to talk to him but he went on ahead just when you called. Oh, Johnny, I do want to find him."

Johnny had never seen Baba so excited.

Suddenly, the passageway ended and they were in a great underground room. Johnny flashed his light around the walls. They, too, were carved with scenes of life on Venus. Beneath each carving was a small doorway leading into a side room. There was one large doorway opposite the one through which they had entered.

"It looks like a meeting house," Johnny said. "With seats and everything." He flashed the light on one of the carvings. He had heard of carvings like these and had seen one once. His father said that they must have been made by an intelligent life form that had visited Venus from the stars. This cave must have been where they had hidden from the animals, just as men now hid from them behind the settlement's great walls. Johnny was awed.

"Johnny, don't just stand here," Baba clicked. "We've got to find him!"

Johnny looked from opening to opening.

"Which way, Baba?"

The little bear sniffed the air. "I can't tell," he said. "I can't tell." Hurriedly they made a circle about the great room. When they came to the large opening, Baba sniffed carefully.

"Maybe here," he clicked, and plunged through.

Down they went as before. This time Johnny grabbed Baba's harness and they were able to move faster. This corridor was just as steep and curving as the first one.

In a few minutes they emerged into another room. It was smaller than the room above and had three small doorways and one large opening.

"Let's try them all," Baba said. Through each of the three small doorways they entered similar rooms. The fourth opening was another corridor. Again Baba thought he smelled the path of the marva.

Down that corridor they went, down and down. Finally it ended in hundreds of the rooms, large and small, the rock was like a honeycomb. Johnny's flashlight was already growing dim, and they didn't dare try to search much longer.

Trying to follow the scent they took a side corridor that led from one small room to another, and came out into a narrow passageway. A faint light glimmered at the end of it. Baba bounded on ahead, Johnny running to keep up with him.

The light seeped through a pile of rocks. Johnny flashed his light through one of the cracks. Behind the pile of rocks the tunnel continued for several feet. In the light of his flashlight Johnny could see bits of leather on the floor of the outer part of the cave. Just beyond them on the other side of the rocks was the cave Johnny and Baba had rested in while climbing up, the cave in which they had cut the long straps they had used to tie themselves together for the long climb upward. The bits of leather on the floor were scraps that had been left over.

"Why, we're almost to the bottom," Johnny said.

"Yes," Baba clicked. "I guess we can't find him. I don't smell anything now but arrow-birds," he ended sadly.

"We gotta try," Johnny said firmly. He felt hollow inside when he thought Baba might go away for good, but he was convinced now that this was the only way to keep him safe.

"Let's try farther down." Johnny turned around and a few minutes later they were going down one of the curving main corridors again.

This corridor gradually straightened out. Soon it hardly slanted down at all. It finally turned into what seemed to be a long underground tunnel. Johnny had to stoop over to keep from hitting his head on the ceiling.

The passageway was no longer going through solid rock, and its walls and floor were a sticky clay. Johnny's and Baba's feet made squishing noises as they walked. It seemed as if the tunnel would never end. They walked on and on.

"I think we're going away from New Plymouth Rock," Baba clicked.

"I think so, too," Johnny answered. "We must've already gone 'most a mile."

The walls had narrowed until Johnny and Baba had to walk single file. Suddenly the passageway slanted upward and a faint glow of light could be seen far away. As they began to climb toward the light the ceiling became so low Johnny had to crawl on his hands and knees. It was a long, sticky climb.

As they approached within a few yards of the light, Baba stopped, blocking Johnny's way.

"This cave must end up in the jungle outside the colony wall," the little bear clicked. "Maybe we ought to stop." He sounded worried.

But Johnny was not going to let this chance pass.

"Go on," he urged.

"But the rhinosaurs...."

"Who's afraid of an old rhinosaur?" Johnny demanded.

"You are," Baba clicked. But he scrambled on.

They emerged into the blinding light in the center of a tangle of thick, high brush. They were out in the jungle, far away from the rock!

The boy and his bear were covered with mud from head to foot. They peered carefully around, listening. In the distance they could hear the rumble of moving rhinosaurs.

As they crept away from the cave, their view continued to be blocked by large bushes and trees. They couldn't even see New Plymouth Rock. Stepping quietly and carefully they finally came to an opening in the brush. Far to the right was the Rock—and, farther in the distance, a guard tower.

"Get back," Johnny shouted. "The guard will see us." The two jumped back.

There was a grunt behind them. They turned. Behind a screen of brush, a great blue-scaled rhinosaur was waking up. It was between them and the opening to the cave. It snorted with the sound of a deep bass drum, and heaved up on its feet.

Ahead, at the edge of the clearing, was a tall meat tree. They had two chances. They could turn quietly and creep away into the brush, hoping the big beast would not see or hear them. Or, they could make a run for the meat tree—in full view of the guard tower.