It was like an Earth forest in the fall, but it was not fall. The forest leaves were green and copper and purple and fiery red, and a wind sent patches of bright greenish sunlight dancing among the leaf shadows.

The hunt party of the Explorer filed along the narrow trail, guns ready, walking carefully, listening to the distant, half familiar cries of strange birds.

A faint crackle of static in their earphones indicated that a gun had been fired.

“Got anything?” asked June Walton. The helmet intercom carried her voice to the ears of the others without breaking the stillness of the forest.

“Took a shot at something,” explained George Barton’s cheerful voice in her earphones. She rounded a bend of the trail and came upon Barton standing peering up into the trees, his gun still raised. “It looked like a duck.”

“This isn’t Central Park,” said Hal Barton, his brother, coming into sight. His green spacesuit struck an incongruous note against the bronze and red forest. “They won’t all look like ducks,” he said soberly.

“Maybe some will look like dragons. Don’t get eaten by a dragon, June,” came Max’s voice quietly into her earphones. “Not while I still love you.” He came out of the trees carrying the blood sample kit, and touched her glove with his, the grin on his ugly beloved face barely visible in the mingled light and shade. A patch of sunlight struck a greenish glint from his fishbowl helmet.

They walked on. A quarter of a mile back, the space ship Explorer towered over the forest like a tapering skyscraper, and the people of the ship looked out of the viewplates at fresh winds and sunlight and clouds, and they longed to be outside.

But the likeness to Earth was danger, and the cool wind might be death, for if the animals were like Earth animals, their diseases might be like Earth diseases, alike enough to be contagious, different enough to be impossible to treat. There was warning enough in the past. Colonies had vanished, and traveled spaceways drifted with the corpses of ships which had touched on some plague planet.

The people of the ship waited while their doctors, in airtight spacesuits, hunted animals to test them for contagion.

The four medicos, for June Walton was also a doctor, filed through the alien homelike forest, walking softly, watching for motion among the copper and purple shadows.

They saw it suddenly, a lighter moving copper patch among the darker browns. Reflex action swung June’s gun into line, and behind her someone’s gun went off with a faint crackle of static, and made a hole in the leaves beside the specimen. Then for a while no one moved.

This one looked like a man, a magnificently muscled, leanly graceful, humanlike animal. Even in its callused bare feet, it was a head taller than any of them. Red-haired, hawk-faced and darkly tanned, it stood breathing heavily, looking at them without expression. At its side hung a sheath knife, and a crossbow was slung across one wide shoulder.

They lowered their guns.

“It needs a shave,” Max said reasonably in their earphones, and he reached up to his helmet and flipped the switch that let his voice be heard. “Something we could do for you, Mac?”

The friendly drawl was the first voice that had broken the forest sounds. June smiled suddenly. He was right. The strict logic of evolution did not demand beards; therefore a non-human would not be wearing a three day growth of red stubble.

Still panting, the tall figure licked dry lips and spoke. “Welcome to Minos. The Mayor sends greetings from Alexandria.”

“English?” gasped June.

“We were afraid you would take off again before I could bring word to you ... It’s three hundred miles ... We saw your scout plane pass twice, but we couldn’t attract its attention.”

June looked in stunned silence at the stranger leaning against the tree. Thirty-six light years--thirty-six times six trillion miles of monotonous space travel--to be told that the planet was already settled! “We didn’t know there was a colony here,” she said. “It is not on the map.”

“We were afraid of that,” the tall bronze man answered soberly. “We have been here three generations and yet no traders have come.”

Max shifted the kit strap on his shoulder and offered a hand. “My name is Max Stark, M.D. This is June Walton, M.D., Hal Barton, M.D., and George Barton, Hal’s brother, also M.D.”

“Patrick Mead is the name,” smiled the man, shaking hands casually. “Just a hunter and bridge carpenter myself. Never met any medicos before.”

The grip was effortless but even through her airproofed glove June could feel that the fingers that touched hers were as hard as padded steel.

“What--what is the population of Minos?” she asked.

He looked down at her curiously for a moment before answering. “Only one hundred and fifty.” He smiled. “Don’t worry, this isn’t a city planet yet. There’s room for a few more people.” He shook hands with the Bartons quickly. “That is--you are people, aren’t you?” he asked startlingly.

“Why not?” said Max with a poise that June admired.

“Well, you are all so--so--” Patrick Mead’s eyes roamed across the faces of the group. “So varied.”

They could find no meaning in that, and stood puzzled.

“I mean,” Patrick Mead said into the silence, “all these--interesting different hair colors and face shapes and so forth--” He made a vague wave with one hand as if he had run out of words or was anxious not to insult them.

“Joke?” Max asked, bewildered.

June laid a hand on his arm. “No harm meant,” she said to him over the intercom. “We’re just as much of a shock to him as he is to us.”

She addressed a question to the tall colonist on outside sound. “What should a person look like, Mr. Mead?”

He indicated her with a smile. “Like you.”

June stepped closer and stood looking up at him, considering her own description. She was tall and tanned, like him; had a few freckles, like him; and wavy red hair, like his. She ignored the brightly humorous blue eyes.

“In other words,” she said, “everyone on the planet looks like you and me?”

Patrick Mead took another look at their four faces and began to grin. “Like me, I guess. But I hadn’t thought of it before. I did not think that people could have different colored hair or that noses could fit so many ways onto faces. I was judging by my own appearance, but I suppose any fool can walk on his hands and say the world is upside down!” He laughed and sobered. “But then why wear spacesuits? The air is breathable.”

“For safety,” June told him. “We can’t take any chances on plague.”

Pat Mead was wearing nothing but a loin cloth and his weapons, and the wind ruffled his hair. He looked comfortable, and they longed to take off the stuffy spacesuits and feel the wind against their own skins. Minos was like home, like Earth ... But they were strangers.

“Plague,” Pat Mead said thoughtfully. “We had one here. It came two years after the colony arrived and killed everyone except the Mead families. They were immune. I guess we look alike because we’re all related, and that’s why I grew up thinking that it is the only way people can look.”

Plague. “What was the disease?” Hal Barton asked.

“Pretty gruesome, according to my father. They called it the melting sickness. The doctors died too soon to find out what it was or what to do about it.”

“You should have trained for more doctors, or sent to civilization for some.” A trace of impatience was in George Barton’s voice.

Pat Mead explained patiently, “Our ship, with the power plant and all the books we needed, went off into the sky to avoid the contagion, and never came back. The crew must have died.” Long years of hardship were indicated by that statement, a colony with electric power gone and machinery stilled, with key technicians dead and no way to replace them. June realized then the full meaning of the primitive sheath knife and bow.

“Any recurrence of melting sickness?” asked Hal Barton.

“No.”

“Any other diseases?”

“Not a one.”

Max was eyeing the bronze red-headed figure with something approaching awe. “Do you think all the Meads look like that?” he said to June on the intercom. “I wouldn’t mind being a Mead myself!”

Their job had been made easy by the coming of Pat. They went back to the ship laughing, exchanging anecdotes with him. There was nothing now to keep Minos from being the home they wanted, except the melting sickness, and, forewarned against it, they could take precautions.

The polished silver and black column of the Explorer seemed to rise higher and higher over the trees as they neared it. Then its symmetry blurred all sense of specific size as they stepped out from among the trees and stood on the edge of the meadow, looking up.

“Nice!” said Pat. “Beautiful!” The admiration in his voice was warming.

“It was a yacht,” Max said, still looking up, “second hand, an old-time beauty without a sign of wear. Synthetic diamond-studded control board and murals on the walls. It doesn’t have the new speed drives, but it brought us thirty-six light years in one and a half subjective years. Plenty good enough.”

The tall tanned man looked faintly wistful, and June realized that he had never had access to a full library, never seen a movie, never experienced luxury. He had been born and raised on Minos.

“May I go aboard?” Pat asked hopefully.

Max unslung the specimen kit from his shoulder, laid it on the carpet of plants that covered the ground and began to open it.

“Tests first,” Hal Barton said. “We have to find out if you people still carry this so-called melting sickness. We’ll have to de-microbe you and take specimens before we let you on board. Once on, you’ll be no good as a check for what the other Meads might have.”

Max was taking out a rack and a stand of preservative bottles and hypodermics.

“Are you going to jab me with those?” Pat asked with interest.

“You’re just a specimen animal to me, bud!” Max grinned at Pat Mead, and Pat grinned back. June saw that they were friends already, the tall pantherish colonist, and the wry, black-haired doctor. She felt a stab of guilt because she loved Max and yet could pity him for being smaller and frailer than Pat Mead.

“Lie down,” Max told him, “and hold still. We need two spinal fluid samples from the back, a body cavity one in front, and another from the arm.”

Pat lay down obediently. Max knelt, and, as he spoke, expertly swabbed and inserted needles with the smooth speed that had made him a fine nerve surgeon on Earth.

High above them the scout helioplane came out of an opening in the ship and angled off toward the west, its buzz diminishing. Then, suddenly, it veered and headed back, and Reno Unrich’s voice came tinnily from their earphones:

“What’s that you’ve got? Hey, what are you docs doing down there?” He banked again and came to a stop, hovering fifty feet away. June could see his startled face looking through the glass at Pat.

Hal Barton switched to a narrow radio beam, explained rapidly and pointed in the direction of Alexandria. Reno’s plane lifted and flew away over the odd-colored forest.

“The plane will drop a note on your town, telling them you got through to us,” Hal Barton told Pat, who was sitting up watching Max dexterously put the blood and spinal fluids into the right bottles without exposing them to air.

“We won’t be free to contact your people until we know if they still carry melting sickness,” Max added. “You might be immune so it doesn’t show on you, but still carry enough germs--if that’s what caused it--to wipe out a planet.”

“If you do carry melting sickness,” said Hal Barton, “we won’t be able to mingle with your people until we’ve cleared them of the disease.”

“Starting with me?” Pat asked.

“Starting with you,” Max told him ruefully, “as soon as you step on board.”

“More needles?”

“Yes, and a few little extras thrown in.”

“Rough?”

“It isn’t easy.”

A few minutes later, standing in the stalls for spacesuit decontamination, being buffeted by jets of hot disinfectant, bathed in glares of sterilizing ultraviolet radiation, June remembered that and compared Pat Mead’s treatment to theirs.

In the Explorer, stored carefully in sealed tanks and containers, was the ultimate, multi-purpose cureall. It was a solution of enzymes so like the key catalysts of the human cell nucleus that it caused chemical derangement and disintegration in any non-human cell. Nothing could live in contact with it but human cells; any alien intruder to the body would die. Nucleocat Cureall was its trade name.

But the cureall alone was not enough for complete safety. Plagues had been known to slay too rapidly and universally to be checked by human treatment. Doctors are not reliable; they die. Therefore spaceways and interplanetary health law demanded that ship equipment for guarding against disease be totally mechanical in operation, rapid and efficient.

Somewhere near them, in a series of stalls which led around and around like a rabbit maze, Pat was being herded from stall to stall by peremptory mechanical voices, directed to soap and shower, ordered to insert his arm into a slot which took a sample of his blood, given solutions to drink, bathed in germicidal ultraviolet, shaken by sonic blasts, breathing air thick with sprays of germicidal mists, being directed to put his arms into other slots where they were anesthesized and injected with various immunizing solutions.

Finally, he would be put in a room of high temperature and extreme dryness, and instructed to sit for half an hour while more fluids were dripped into his veins through long thin tubes.

All legal spaceships were built for safety. No chance was taken of allowing a suspected carrier to bring an infection on board with him.

June stepped from the last shower stall into the locker room, zipped off her spacesuit with a sigh of relief, and contemplated herself in a wall mirror. Red hair, dark blue eyes, tall...

“I’ve got a good figure,” she said thoughtfully.

Max turned at the door. “Why this sudden interest in your looks?” he asked suspiciously. “Do we stand here and admire you, or do we finally get something to eat?”

“Wait a minute.” She went to a wall phone and dialed it carefully, using a combination from the ship’s directory. “How’re you doing, Pat?”

The phone picked up a hissing of water or spray. There was a startled chuckle. “Voices, too! Hello, June. How do you tell a machine to go jump in the lake?”

“Are you hungry?”

“No food since yesterday.”

“We’ll have a banquet ready for you when you get out,” she told Pat and hung up, smiling. Pat Mead’s voice had a vitality and enjoyment which made shipboard talk sound like sad artificial gaiety in contrast.

They looked into the nearby small laboratory where twelve squealing hamsters were protestingly submitting to a small injection each of Pat’s blood. In most of them the injection was followed by one of antihistaminics and adaptives. Otherwise the hamster defense system would treat all non-hamster cells as enemies, even the harmless human blood cells, and fight back against them violently.

One hamster, the twelfth, was given an extra large dose of adaptive, so that if there were a disease, he would not fight it or the human cells, and thus succumb more rapidly.

“How ya doing, George?” Max asked.

“Routine,” George Barton grunted absently.

On the way up the long spiral ramps to the dining hall, they passed a viewplate. It showed a long scene of mountains in the distance on the horizon, and between them, rising step by step as they grew farther away, the low rolling hills, bronze and red with patches of clear green where there were fields.

Someone was looking out, standing very still, as if she had been there a long time--Bess St. Clair, a Canadian woman. “It looks like Winnipeg,” she told them as they paused. “When are you doctors going to let us out of this blithering barberpole? Look,” she pointed. “See that patch of field on the south hillside, with the brook winding through it? I’ve staked that hillside for our house. When do we get out?”

Reno Ulrich’s tiny scout plane buzzed slowly in from the distance and began circling lazily.

“Sooner than you think,” Max told her. “We’ve discovered a castaway colony on the planet. They’ve done our tests for us by just living here. If there’s anything here to catch, they’ve caught it.”

“People on Minos?” Bess’s handsome ruddy face grew alive with excitement.

“One of them is down in the medical department,” June said. “He’ll be out in twenty minutes.”

“May I go see him?”

“Sure,” said Max. “Show him the way to the dining hall when he gets out. Tell him we sent you.”

“Right!” She turned and ran down the ramp like a small girl going to a fire. Max grinned at June and she grinned back. After a year and a half of isolation in space, everyone was hungry for the sight of new faces, the sound of unfamiliar voices.

They climbed the last two turns to the cafeteria, and entered to a rich subdued blend of soft music and quiet conversations. The cafeteria was a section of the old dining room, left when the rest of the ship had been converted to living and working quarters, and it still had the original finely grained wood of the ceiling and walls, the sound absorbency, the soft music spools and the intimate small light at each table where people leisurely ate and talked.

They stood in line at the hot foods counter, and behind her June could hear a girl’s voice talking excitedly through the murmur of conversation.

“--new man, honest! I saw him through the viewplate when they came in. He’s down in the medical department. A real frontiersman.”

The line drew abreast of the counters, and she and Max chose three heaping trays, starting with hydroponic mushroom steak, raised in the growing trays of water and chemicals; sharp salad bowl with rose tomatoes and aromatic peppers; tank-grown fish with special sauce; four different desserts, and assorted beverages.

Presently they had three tottering trays successfully maneuvered to a table. Brant St. Clair came over. “I beg your pardon, Max, but they are saying something about Reno carrying messages to a colony of savages, for the medical department. Will he be back soon, do you know?”

Max smiled up at him, his square face affectionate. Everyone liked the shy Canadian. “He’s back already. We just saw him come in.”

“Oh, fine.” St. Clair beamed. “I had an appointment with him to go out and confirm what looks like a nice vein of iron to the northeast. Have you seen Bess? Oh--there she is.” He turned swiftly and hurried away.

A very tall man with fiery red hair came in surrounded by an eagerly talking crowd of ship people. It was Pat Mead. He stood in the doorway, alertly scanning the dining room. Sheer vitality made him seem even larger than he was. Sighting June, he smiled and began to thread toward their table.

“Look!” said someone. “There’s the colonist!” Shelia, a pretty, jeweled woman, followed and caught his arm. “Did you really swim across a river to come here?”

Overflowing with good-will and curiosity, people approached from all directions. “Did you actually walk three hundred miles? Come, eat with us. Let me help choose your tray.”

Everyone wanted him to eat at their table, everyone was a specialist and wanted data about Minos. They all wanted anecdotes about hunting wild animals with a bow and arrow.

“He needs to be rescued,” Max said. “He won’t have a chance to eat.”

June and Max got up firmly, edged through the crowd, captured Pat and escorted him back to their table. June found herself pleased to be claiming the hero of the hour.

Pat sat in the simple, subtly designed chair and leaned back almost voluptuously, testing the way it gave and fitted itself to him. He ran his eyes over the bright tableware and heaped plates. He looked around at the rich grained walls and soft lights at each table. He said nothing, just looking and feeling and experiencing.

“When we build our town and leave the ship,” June explained, “we will turn all the staterooms back into the lounges and ballrooms and cocktail bars that used to be inside.”

“Oh, I’m not complaining,” Pat said negligently. He cocked his head to the music, and tried to locate its source.

“That’s big of you,” said Max with gentle irony.

They fell to, Pat beginning the first meal he had had in more than a day.

Most of the other diners finished when they were halfway through, and began walking over, diffidently at first, then in another wave of smiling faces, handshakes, and introductions. Pat was asked about crops, about farming methods, about rainfall and floods, about farm animals and plant breeding, about the compatibility of imported Earth seeds with local ground, about mines and strata.

There was no need to protect him. He leaned back in his chair and drawled answers with the lazy ease of a panther; where he could think of no statistic, he would fill the gap with an anecdote. It developed that he enjoyed spinning campfire yarns and especially being the center of interest.

Between bouts of questions, he ate with undiminished and glowing relish.

June noticed that the female specialists were prolonging the questions more than they needed, clustering around the table laughing at his jokes, until presently Pat was almost surrounded by pretty faces, eager questions, and chiming laughs. Shelia the beautiful laughed most chimingly of all.

June nudged Max, and Max shrugged indifferently. It wasn’t anything a man would pay attention to, perhaps. But June watched Pat for a moment more, then glanced uneasily back to Max. He was eating and listening to Pat’s answers and did not feel her gaze. For some reason Max looked almost shrunken to her. He was shorter than she had realized; she had forgotten that he was only the same height as herself. She was dimly aware of the clear lilting chatter of female voices increasing at Pat’s end of the table.

“That guy’s a menace,” Max said, and laughed to himself, cutting another slice of hydroponic mushroom steak. “What’s eating you?” he added, glancing aside at her when he noticed her sudden stillness.

“Nothing,” she said hastily, but she did not turn back to watching Pat Mead. She felt disloyal. Pat was only a superb animal. Max was the man she loved. Or--was he? Of course he was, she told herself angrily. They had gone colonizing together because they wanted to spend their lives together; she had never thought of marrying any other man. Yet the sense of dissatisfaction persisted, and along with it a feeling of guilt.

Len Marlow, the protein tank-culture technician responsible for the mushroom steaks, had wormed his way into the group and asked Pat a question. Now he was saying, “I don’t dig you, Pat. It sounds like you’re putting the people into the tanks instead of the vegetables!” He glanced at them, looking puzzled. “See if you two can make anything of this. It sounds medical to me.”

Pat leaned back and smiled, sipping a glass of hydroponic burgundy. “Wonderful stuff. You’ll have to show us how to make it.”

Len turned back to him. “You people live off the country, right? You hunt and bring in steaks and eat them, right? Well, say I have one of those steaks right here and I want to eat it, what happens?”

“Go ahead and eat it. It just wouldn’t digest. You’d stay hungry.”

“Why?” Len was aggrieved.

“Chemical differences in the basic protoplasm of Minos. Different amino linkages, left-handed instead of right-handed molecules in the carbohydrates, things like that. Nothing will be digestible here until you are adapted chemically by a little test-tube evolution. Till then you’d starve to death on a full stomach.”

Pat’s side of the table had been loaded with the dishes from two trays, but it was almost clear now and the dishes were stacked neatly to one side. He started on three desserts, thoughtfully tasting each in turn.

“Test-tube evolution?” Max repeated. “What’s that? I thought you people had no doctors.”

“It’s a story.” Pat leaned back again. “Alexander P. Mead, the head of the Mead clan, was a plant geneticist, a very determined personality and no man to argue with. He didn’t want us to go through the struggle of killing off all Minos plants and putting in our own, spoiling the face of the planet and upsetting the balance of its ecology. He decided that he would adapt our genes to this planet or kill us trying. He did it all right.’”

“Did which?” asked June, suddenly feeling a sourceless prickle of fear.

“Adapted us to Minos. He took human cells--”

She listened intently, trying to find a reason for fear in the explanation. It would have taken many human generations to adapt to Minos by ordinary evolution, and that only at a heavy toll of death and hunger which evolution exacts. There was a shorter way: Human cells have the ability to return to their primeval condition of independence, hunting, eating and reproducing alone.

Alexander P. Mead took human cells and made them into phagocytes. He put them through the hard savage school of evolution--a thousand generations of multiplication, hardship and hunger, with the alien indigestible food always present, offering its reward of plenty to the cell that reluctantly learned to absorb it.

“Leucocytes can run through several thousand generations of evolution in six months,” Pat Mead finished. “When they reached to a point where they would absorb Minos food, he planted them back in the people he had taken them from.”

“What was supposed to happen then?” Max asked, leaning forward.

“I don’t know exactly how it worked. He never told anybody much about it, and when I was a little boy he had gone loco and was wandering ha-ha-ing around waving a test tube. Fell down a ravine and broke his neck at the age of eighty.”

“A character,” Max said.

Why was she afraid? “It worked then?”

“Yes. He tried it on all the Meads the first year. The other settlers didn’t want to be experimented on until they saw how it worked out. It worked. The Meads could hunt, and plant while the other settlers were still eating out of hydroponics tanks.”

“It worked,” said Max to Len. “You’re a plant geneticist and a tank culture expert. There’s a job for you.”

“Uh-uh!” Len backed away. “It sounds like a medical problem to me. Human cell control--right up your alley.”

“It is a one-way street,” Pat warned. “Once it is done, you won’t be able to digest ship food. I’ll get no good from this protein. I ate it just for the taste.”

Hal Barton appeared quietly beside the table. “Three of the twelve test hamsters have died,” he reported, and turned to Pat. “Your people carry the germs of melting sickness, as you call it. The dead hamsters were injected with blood taken from you before you were de-infected. We can’t settle here unless we de-infect everybody on Minos. Would they object?”

“We wouldn’t want to give you folks germs,” Pat smiled. “Anything for safety. But there’ll have to be a vote on it first.”

The doctors went to Reno Ulrich’s table and walked with him to the hangar, explaining. He was to carry the proposal to Alexandria, mingle with the people, be persuasive and wait for them to vote before returning. He was to give himself shots of cureall every two hours on the hour or run the risk of disease.

Reno was pleased. He had dabbled in sociology before retraining as a mechanic for the expedition. “This gives me a chance to study their mores.” He winked wickedly. “I may not be back for several nights.” They watched through the viewplate as he took off, and then went over to the laboratory for a look at the hamsters.

Three were alive and healthy, munching lettuce. One was the control; the other two had been given shots of Pat’s blood from before he entered the ship, but with no additional treatment. Apparently a hamster could fight off melting sickness easily if left alone. Three were still feverish and ruffled, with a low red blood count, but recovering. The three dead ones had been given strong shots of adaptive and counter histamine, so their bodies had not fought back against the attack.

June glanced at the dead animals hastily and looked away again. They lay twisted with a strange semi-fluid limpness, as if ready to dissolve. The last hamster, which had been given the heaviest dose of adaptive, had apparently lost all its hair before death. It was hairless and pink, like a still-born baby.

“We can find no micro-organisms,” George Barton said. “None at all. Nothing in the body that should not be there. Leucosis and anemia. Fever only for the ones that fought it off.” He handed Max some temperature charts and graphs of blood counts.

June wandered out into the hall. Pediatrics and obstetrics were her field; she left the cellular research to Max, and just helped him with laboratory routine. The strange mood followed her out into the hall, then abruptly lightened.