The biped took off her helmet and suit and hung them in a closet. The door slid open as she approached and closed when she walked away.

She signaled that he could remove his suit. He did not hesitate. Though the air might be poisonous, he had no choice. His tank would soon be empty. Moreover, it seemed likely that the atmosphere contained enough oxygen. Even then he had grasped the idea that the leaves of the umbrella plants, which grew out of the top of the tubes, absorbed sunlight and traces of carbon dioxide. Inside the tunnels, the roots drew up water from the channel and absorbed the great quantity of carbon dioxide released by the dekapeds. Energy of sunlight converted gas and liquid into glucose and oxygen, which were given off in the tunnels.

Even here, in this deep chamber which lay beneath and to one side of the tube, a thick root penetrated the ceiling and spread its thin white web over the walls. He stood directly beneath the fleshy growth as he removed his helmet and took his first breath of Martian air. Immediately afterward, he jumped. Something wet had dropped on his forehead. Looking up, he saw that the root was excreting liquid from a large pore. He wiped the drop off with his finger and tasted it. It was sticky and sweet.

Well, he thought, the tree must normally drop sugar in water. But it seemed to be doing so abnormally fast, because another drop was forming.

Then it came to him that perhaps this was so because it was getting dark outside and therefore cold. The umbrella trees might be pumping the water in their trunks into the warm tunnels. Thus, during the bitter subzero night, they'd avoid freezing and swelling up and cracking wide open.

It seemed a reasonable theory.

He looked around. The place was half living quarters, half biological laboratory. There were beds and tables and chairs and several unidentifiable articles. One was a large black metal box in a corner. From it, at regular intervals, issued a stream of tiny blue bubbles. They rose to the ceiling, growing larger as they did so. On reaching the ceiling they did not stop or burst but simply penetrated the vitrification as if it did not exist.

Lane now knew the origin of the blue globes he had seen appear from the surface of the garden. But their purpose was still obscure.

He wasn't given much time to watch the globes. The biped took a large green ceramic bowl from a cupboard and set it on a table. Lane eyed her curiously, wondering what she was going to do. By now he had seen that the second head belonged to an entirely separate creature. Its slim four-foot length of pinkish skin was coiled about her neck and torso; its tiny flat-faced head turned toward Lane; its snaky light blue eyes glittered. Suddenly, its mouth opened and revealed toothless gums, and its bright red tongue, mammalian, not at all reptilian, thrust out at him.

The biped, paying no attention to the worm's actions, lifted it from her. Gently, cooing a few words in a soft many-voweled language, she placed it in the bowl. It settled inside and looped around the curve, like a snake in a pit.

The biped took a pitcher from the top of a box of red plastic. Though the box was not connected to any visible power source, it seemed to be a stove. The pitcher contained warm water which she poured into the bowl, half filling it. Under the shower, the worm closed its eyes as if it were purring soundless ecstasy.

Then the biped did something that alarmed Lane.

She leaned over the bowl and vomited into it.

He stepped toward her. Forgetting the fact that she couldn't understand him, he said, "Are you sick?"

She revealed human-looking teeth in a smile meant to reassure him, and she walked away from the bowl. He looked at the worm, which had its head dipped into the mess. Suddenly, he felt sick, for he was sure that it was feeding off the mixture. And he was equally certain that she fed the worm regularly with regurgitated food.

It didn't cancel his disgust to reflect that he shouldn't react to her as he would to a Terrestrial. He knew that she was totally alien and that it was inevitable that some of her ways would repel, perhaps even shock him. Rationally, he knew this. But if his brain told him to understand and forgive, his belly said to loathe and reject.

His aversion was not much lessened by a close scrutiny of her as she took a shower in a cubicle set in the wall. She was about five feet tall and slim as a woman should be slim, with delicate bones beneath rounded flesh. Her legs were human; in nylons and high heels they would have been exciting -- other things being equal. However, if the shoes had been toeless, her feet would have caused much comment. They had four toes.

Her long beautiful hands had five fingers. These seemed nailless, like the toes, though a closer examination later showed him they did bear rudimentary nails.

She stepped from the cubicle and began toweling herself, though not before she motioned to him to remove his suit and also to shower. He stared intently back at her until she laughed a short embarrassed laugh. It was feminine, not at all deep. Then she spoke.

He closed his eyes and was hearing what he had thought he would not hear for years: a woman's voice. Hers was extraordinary: husky and honeyed at the same time.

But when he opened his eyes, he saw her for what she was. No woman. No man. What? It? No. The impulse to think her, she, was too strong.

This, despite her lack of mammaries. She had a chest, but no nipples, rudimentary or otherwise. Her chest was a man's, muscled under the layer of fat which subtly curved to give the impression that beneath it... budding breasts?

No, not this creature. She would never suckle her young. She did not even bear them alive, if she did bear. Her belly was smooth, undimpled with a navel.

Smooth also was the region between her legs, hairless, unbroken, as innocent of organ as if she were a nymph painted for some Victorian children's book.

It was that sexless joining of the legs that was so horrible. Like the white belly of a frog, thought Lane, shuddering.

At the same time, his curiosity became even stronger. How did this thing mate and reproduce?

Again she laughed and smiled with fleshy pale-red humanly everted lips and wrinkled a short, slightly uptilted nose and ran her hand through thick straight red-gold fur. It was fur, not hair, and it had a slightly oily sheen, like a water-dwelling animal's.

The face itself, though strange, could have passed for human, but only passed. Her cheekbones were very high and protruded upward in an unhuman fashion. Her eyes were dark blue and quite human. This meant nothing. So were an octopus' eyes.

She walked to another closet, and as she went away from him he saw again that though the hips were curved like a woman's they did not sway with the pelvic displacement of the human female.

The door swung momentarily open, revealed the carcasses of several dekapeds, minus their legs, hanging on hooks. She removed one, placed it on a metal table, and out of the cupboard took a saw and several knives and began cutting.

Because he was eager to see the anatomy of the dekaped, he approached the table. She waved him to the shower. Lane removed his suit. When he came to the knife and ax he hesitated, but, afraid she might think him distrustful, he hung up the belt containing his weapons beside the suit. However, he did not take off his clothes because he was determined to view the inner organs of the animal. Later, he would shower.

The legger was not an insect, despite its spidery appearance. Not in the Terrestrial sense, certainly. Neither was it a vertebrate. Its smooth hairless skin was an animal's, as lightly pigmented as a blond Swede's. But, though it had an endoskeleton, it had no backbone. Instead, the body bones formed a round cage. Its thin ribs radiated from a cartilaginous collar which adjoined the back of the head. The ribs curved outward, then in, almost meeting at the posterior. Inside the cage were ventral lung sacs, a relatively large heart, and liver-like and kidney-like organs. Three arteries, instead of the mammalian two, left the heart. He couldn't be sure with such a hurried examination, but it looked as if the dorsal aorta, like some Terrestrial reptiles, carried both pure and impure blood.