As before, the cold did not last more than six or seven hours, and the snow did not stick to the ground. They weathered it better this time, finding that the blimpsilk clothes were more protective than they looked, working as windbreakers.

The thirtieth day since their emergence was marked by two things: something that happened, and something that didn't happen.

The first was their arrival at the confluence of the Clio and the mighty river Ophion. They were deep in south Hyperion by then, equidistant between the central vertical cable and the southern one, both of which now towered over them.

Ophion was blue-green, wider and swifter than the Clio. It swept Titanic into its center, and after a time of alertness and soundings with their poles, the travelers decided it would be safe to stay there. In size and speed, Ophion reminded Bill and Cirocco of the Mississippi, but with more vegetation and tall trees along the banks. The land was still jungle, but Ophion was wide and deep.

Cirocco was far more concerned with the non-event--- the one she had waited for as the days ticked by on Calvin's watch. She had been regular as the tides for twenty-two years, and it was disturbing to miss a period.

"Did you know it's been thirty days now?" Cirocco asked Gaby that evening."

"Has it? I hadn't thought about it." She frowned.

"Yeah. And I'm more than late. I've always been twenty-nine days; sometimes early by a day, never late."

"You know, I'm late, too." "I thought you were."

"Christ, that just doesn't make sense at all."

"I was wondering what sort of protection you used on Ring- master. Could you have forgotten about it back then?"

"Not bloody likely. Calvin gave me monthlies."

Cirocco sighed. "I was afraid it'd be something as infallible as that. Me, I can't take pills; they make me swell up. I used one of those wear-ever diaphragms. I had it in when we went under. I didn't really think to look for it until ... well, after we joined up with Bill and August and it might already have been too late." She was hesitant to discuss that part with Gaby. It was no secret that she and Bill had made love, and also no secret that there had been no time or place or privacy for it on Titanic with Gaby always around.

"Anyhow, it's gone. I presume it was eaten by the same thing that ate our hair. Which makes my skin crawl, by the way,"

Gaby shivered.

"But I thought it could be Bill. Now I don't really think so." She got up and went over to Bill, who was sleeping on the ground. She woke him, and waited until he looked alert.

"Bill, we're both pregnant."

Bill was not as awake as she had thought. He blinked in surprise, then his brow furrowed.

"Well don't look at me. Not even for yours. The last time with Gaby was not long after we left Earth. Besides, I've got a valve."

"I wasn't saying anything like that," she soothed. With Gaby,

hub? she thought. She hadn't known about that, and she thought she had been aware of everything that occurred on Ring- master. "That just makes it more certain that something very strange is going on. Somebody or something is playing a big joke on us, but I'm not laughing."

Calvin was as good as his word. Two days after Cirocco hailed a passing blimp, Whistlestop hovered overhead and a blue flower blossomed with their wandering surgeon dangling beneath it. August was close behind him. They hit the water just off shore.

Cirocco had to admit that Calvin looked good. He was smiling, and there was a bounce in his step. He greeted everyone and didn't seem to mind having been summoned. He wanted to talk about his travels, but Cirocco was too anxious to hear what he thought of the new situation. He turned very serious long before they had finished telling him about it.

"Have you had a period since we got here?" he asked August. "No, I haven't."

"It's been thirty days," Cirocco said. ',is that unusual for you?" From the way August's eyes widened, Cirocco assumed it was. "When was the last time you had intercourse with a man?"

"I've never."

"I was afraid you'd say that."

Calvin was quiet for a while, considering it. Then he frowned more deeply.

"What can I say? You all know it's possible for a woman to skip a period for other reasons. Athletes sometimes skip a whole lot of them, and we're not sure why. Stress can do it, emotional or physical. But I think the chances of it happening to all three of you at the same time are slim."

"I would tend to agree," Cirocco said.

"It could be dietary. There's no way to know. I can tell you that the three of you, and ... uh, April, were undergoing some convergence."

"What's that?" Gaby asked.

"It sometimes happens to women who live together, like on a spaceship where they're in close quarters. Some hormonal signal tends to synchronize their menstruation. April and August have been in rhythm with each other for a long time, and Cirocco was only a few days off their cycle. Two early periods and she was in step. Gaby, you were getting erratic, if you recall.,,

"I never paid much attention to it," she said.

"Well, you were. But I can't see what that would have to do with what we have here. I only brought it up to point out that strange things happen. It's possible that you all just skipped one."

"It's also possible that we're all knocked up, and I shudder to think who the father is," sirocco said, sourly. .

"That's just flat impossible," Calvin said. "If you're saying that the thing that ate us did it to you all ... I can't buy that. There isn't another animal even on Earth that can impregnate a human. You tell me how this alien creature did it."

"I don't know," Cirocco said. "That's why it's alien. But I'm convinced it got inside us and did something that might seem perfectly reasonable and natural to it, but is alien to what we know. And I don't like it, and we want to know what you can do if we are pregnant."

Calvin rubbed the tight curls on his chin, then smiled slightly. "They didn't prepare me for virgin births at med school."

"I'm not in the mood for jokes."

"Sorry. You and Gaby aren't virgins, anyhow." He shook his head in wonder.

"We were thinking of something more immediate and less sacred, " Gaby said. "We don't want these babies, or whatever the hell they are."

"Look, why don't you wait another thirty days before you start getting excited? If you miss another period, call me again."

"We'd like to get it over with now," Cirocco said.

Calvin looked upset for the first time. "And I'm saying I won't do it yet. It's too risky. I might make the tools for a D. and C., but they'll have to he sterilized. I don't have a speculum, and the thought of what I might have to improvise to dilate the cervix is enough to give you nightmares."

"The thought of what I've got growing in my belly is giving

me nightmares," Cirocco said, darkly. "Calvin, I don't even want a human baby now, much less whatever this might be. I want you to do the operation."

Gaby and August nodded their agreement, though Gaby looked slightly ill.

"And I say wait another month. It won't make any difference. The operation would he the same, just scraping out the inner walls of the uterus. But maybe a month from now you'll have found a way to make a fire, to boil some water, to sterilize whatever instruments I manage to make. Doesn't that make sense? I assure you, I can do the operation with a minimum of risk, but only with clean tools."

"I just want to get it over with," Cirocco said. "I want to get this thing out of me."

"Captain, take it easy. Settle down and think it out. if you get infected, I'm helpless. There's different country to the cast. You ~t find a way to make a fire. I'll look, too. I was clear over in Mnemosyne when your call came. It could be there's somebody who uses tools and could make a decent speculum and dilator."

"Then you're leaving again?" she asked. "Yes, I am, after I give you all a check-up." "I'm asking you again to stay with us."

"I'm sorry. I can't." Nothing Cirocco could say would change his mind, and though she flirted again with the idea of holding him, the same reasons still made that a bad idea. And one more thing had occurred to her since his departure; it might not he wise to harm someone with a friend as big as Whistlestop.

He pronounced all four of them fit and healthy, despite the missed periods of the women, then stayed a few hours, seeming to begrudge even that. He told them what they had seen in their travels.

Oceanus was a terrible place, frozen and forbidding They had crossed it as quickly as possible. There was a humanoid race down there, but Whistlestop would not go down for a close look They had thrown rocks from a wooden catapult even when the

blimp was a kilometer above them. Calvin described them as human in shape, covered with long white hair. They shot first and asked questions later. He called them Yeti.

"Mnemosyne is a desert," he said. "It looks odd, because the dunes stack up a lot higher than on Earth, from the low gravity, I guess. There's plant life down there. I saw some small animals when we went down low, and what looked like a ruined city and a few small towns. Places that might have been castles a thousand years ago perched up on vertical rock spires, crumbling apart. It would have taken a thousand years of coolie labor to build them, or some pretty good helicopters.

"I think something has gone badly wrong in here. It's all going to dust. Mnemosyne might have looked like this place once, right down to the empty river bed and the corpses of huge trees being eaten away by sandstorms. Something changed the climate, or got away from the builders.

'lit was probably this worm we saw. There's only one of them, Whistlestop says. Mnemosyne is only big enough for one. If there were two, they fought it out long ago and only this grand- daddy worm is left. It's big enough to eat Whistlestop like an olive."

Both Cirocco and Bill looked up at Calvin's mention of giant worms.

"I never did see the whole thing, but I wouldn't be surprised if it's twenty kilometers long. It's just a big, long tube, with a hole at both ends as wide as the whole damn worm. It's segmented, and the body looks hard, like an armadillo shell. it's got a mouth like a buzz saw, teeth an the inside and the outside both. it spends its time under the sand, but sometimes it isn't deep enough and it has to come to the surface. We watched it one of those times."