Later that night, as Kerans lay asleep in his bunk at the testing station, the dark waters of the lagoon outside drifting through the drowned city, the first of the dreams came to him. He had left his cabin and walked out on to the deck, looking down over the rail at the black luminous disc of the lagoon. Dense palls of opaque gas swirled across the sky only a few hundred feet overhead, through which he could just discern the faint glimmering outline of a gigantic sun. Booming distantly, it sent dull glows pulsing across the lagoon, momentarily lighting the long limestone cliffs which had taken the place of the ring of white-faced buildings.

Reflecting these intermittent flares, the deep bowl of the water shone in a diffused opalescent blur, the discharged light of myriads of phosphorescing animalcula, congregating in dense shoals like a succession of submerged haloes. Between them the water was thick with thousands of entwined snakes and eels, writhing together in frantic tangles that tore the surface of the lagoon.

As the great sun drummed nearer, almost filling the sky itself, the dense vegetation along the limestone cliffs was flung back abruptly, to reveal the black and stone-grey heads of enormous Triassic lizards. Strutting forward to the edge of the cliffs, they began to roar together at the sun, the noise gradually mounting until it became indistinguishable from the volcanic pounding of the solar flares. Beating within him like his own pulse, Kerans felt the powerful mesmeric pull of the baying reptiles, and stepped out into the lake, whose waters now seemed an extension of his own blood stream. As the dull pounding rose, he felt the barriers which divided his own cells from the surrounding medium dissolving, and he swam forwards, spreading outwards across the black thudding water…

He woke in the suffocating metal box of his cabin, his head splitting like a burst marrow, too exhausted to open his eyes. Even as he sat on the bed, splashing his face in the luke-warm water from the jug, he could still see the vast inflamed disc of the spectral sun, still hear the tremendous drumming of its beat. Timing them, he realised that the frequency was that of his own heartbeats, but in some insane way the sounds were magnified so that they remained just above the auditory threshold, reverberating dimly off the metal walls and ceiling like the whispering murmur of some blind pelagic current against the hull-plates of a submarine.

The sounds seemed to pursue him as he opened the cabin door and moved down the corridor to the galley. It was shortly after 6 a.m. and the testing station stirred with a faint hollowed silence, the first flares of the false dawn illuminating the dusty reagent benches and the crates stacked under the fan-lights in the corridor. Several times Kerans paused and tried to shrug off the echoes that persisted in his ears, uneasily wondering what was the real identity of his new pursuers. His unconscious was rapidly becoming a well-stocked pantheon of tutelary phobias and obsessions, homing onto his already over-burdened psyche like lost telepaths. Sooner or later the archetypes themselves would become restive and start fighting each other, anima against persona, ego against id…

Then he remembered that Beatrice Dahl had seen the same dream and pulled himself together. He went out onto the deck and looked across the slack water of the lagoon at the distant spire of the apartment block, trying to decide whether to borrow one of the scows moored to the jetty and drive over to her. Having now experienced one of the dreams, he realised the courage and self-sufficiency Beatrice had displayed, brushing off the least show of sympathy.

And yet Kerans knew that for some reason he had been reluctant to give Beatrice any real sympathy, cutting his questions about the nightmares as short as possible and never offering her treatment or sedative. Nor had he tried to follow up any of Bodkins' or Riggs' oblique remarks about the dreams and their danger, almost as if he had known that he would soon be sharing them, and accepted them as an inevitable element of his life, like the image of his own death each of them carried with him in the secret places of his heart. (Logically_for what had a more gloomy prognosis than life?-every morning one should say to one's friends: 'I grieve for your irrevocable death', as to anyone suffering from an incurable disease, and was the universal omission of this minimal gesture of sympathy the model for their reluctance to discuss the dreams?)

Bodkin was sitting at the table in the galley when Kerans entered, placidly drinking coffee brewing in a large cracked sauce-pan on the stove. His shrewd quick eyes watched Kerans unobtrusively as he lowered himself into a chair and massaged his forehead slowly with a febrile hand.

"So you're one of the dreamers now, Robert. You've beheld the fata morgana of the terminal lagoon. You look tired. Was it a deep one?

Kerans managed a rueful laugh. "Are you trying to frighten me, Alan? I wouldn't know yet, but it felt deep enough. God, I wish I hadn't spent last night here. There are no nightmares at the Ritz." He sipped pensively at the hot coffee. "So that's what Riggs was talking about. How many of his men are seeing these dreams?"

"Riggs himself doesn't, but at least half the others. And Beatrice Dahl, of course. I've been seeing them for a full three months. It's basically the same recurrent dream in all cases." Bodkin spoke in a slow unhurried voice, with a softer tone than his usual blunt delivery, as if Kerans had now become a member of a select inner group. "You've held out for a long time, Robert, it's quite a tribute to the strength of your preconscious filters. We were all beginning to wonder when you'd arrive." He smiled at Kerans. "Figuratively, of course. I've never discussed the dreams with anyone. Except for Hardman, and there, poor chap, the dreams were having him." As an afterthought he added: "You spotted the sun-pulse equation? Hardman's gramophone record was a play-back of his own pulse, amplified in the hope of precipitating the crisis then and there. Don't think I sent him out into those jungles deliberately."

Kerans nodded and gazed out through the window at the rounded bulk of the floating base moored alongside. High up on the top deck Sergeant Daley, the helicopter co-pilot, was standing motionless by the rail, staring across the cool early morning water. Perhaps he too had just woken from the same corporate nightmare, was filling his eyes with the olive-green spectrum of the lagoon in the forlorn expectation of erasing the burning image of the Triassic sun. Kerans looked down at the dark shadows below the table, seeing again the faint glimmer of the phosphorescing pools. Distantly in his ears he could hear the sun drumming over the sunken water. As he recovered from his first fears he realised that there was something soothing about its sounds, almost reassuring and encouraging like his own heartbeats. But the giant reptiles had been terrifying.

He remembered the iguanas braying and lunging across the steps of the museum. Just as the distinction between the latent and manifest contents of the dream had ceased to be valid, so had any division between the real and the super-real in the external world. Phantoms slid imperceptibly from nightmare to reality and back again, the terrestrial and psychic landscapes were now indistinguishable, as they had been at Hiroshima and Auschwitz, Golgotha and Comorrah.

Sceptical of the remedy, he said to Bodkin: "You'd better lend me Hardman's alarm clock, Alan. Or better still, remind me to take a phenobarbitone tonight."

"Don't," Bodkin warned him firmly. "Not unless you want the impact doubled. Your residues of conscious control are the only thing holding up the dam." He buttoned his cotton jacket around his shirtless chest. "That wasn't a true dream, Robert, but an ancient organic memory millions of years old."

He pointed to the ascending rim of the sun through the groves of gymnospenns. "The innate releasing mechanisms laid down in your cytoplasm millions of years ago have been awakened, the expanding sun and the rising temperature are driving you back down the spinal levels into the drowned seas submerged beneath the lowest layers of your unconscious, into the entirely new zone of the neuronic psyche. This is the lumbar transfer, total biopsychic recall. We really remember these swamps and lagoons. After a few nights you won't be frightened of the dreams, despite their superficial horror. That's why Riggs has received orders for us to leave."

"The Pelycosaur…?" Kerans asked.

Bodkin nodded. "The joke was on us. The reason they didn't take the report seriously at Byrd was that ours wasn't the first to be reported."

Footsteps sounded up the companionway and moved briskly along the metal deck outside. Colonel Riggs pushed back the double swing doors, freshly scrubbed and breakfasted.

He waved his baton at them amiably, eyeing the litter of unwashed cups and his two reclining subordinates.

"God, what a pig hole! Morning to you both. We've got a busy day ahead of us so let's get our elbows off the table. I've fixed the departure time for twelve hundred hours tomorrow, and there'll be a final embarkation stand-by at ten hundred. I don't want to waste any more fuel than I have to, so dump everything you can overboard. You all right, Robert?"

"Perfectly," Kerans replied flatly, sitting up.

"Glad to hear it. You look a bit glassy. Right, then. If you want to borrow the cutter to evacuate the Ritz…"

Kerans listened to him automatically, watching the sun as it rose magnificently behind the gesticulating outline of the Colonel. What completely separated them now was the single fact that Riggs had not seen the dream, not felt its immense hallucinatory power. He was still obeying reason and logic, buzzing around his diminished, unimportant world with his little parcels of instructions like a worker bee about to return to the home nest. After a few minutes he ignored the Colonel completely and listened to the deep subliminal drumming in his ears, half-closed his eyes so that he could see the glimmering surface of the lake dapple across the dark underhang of the table.

Opposite him Bodkin appeared to be doing the same, his hands folded over his navel. During how many of their recent conversations had he in fact been miles away?

When Riggs left, Kerans followed him to the door. "Of course, Colonel, everything will be ready in good time. Thank you for calling."

As the cutter moved off across the lagoon he went back to his chair. For a few minutes the two men stared across the table at each other, the insects outside bouncing off the wire mesh as the sun lifted into the sky. At last Kerans spoke.