It is rather difficult to say exactly what sort of novel The Book of the New Sun is, for Wolfe has quietly and without any fuss invented a new literary form, the continuously recursive picaresque. He has done for picaresque fantasy very much what Escher did for architectural drawing. Just as in an Escher picture, what seems at first to be a wall appears after the onlooker blinks to be a roof or a floor, while downhill stairways mount ever higher, so in Wolfe the surface elements of the picaresque (the hero sets out on a quest and has a series of adventures before becoming king) rearrange themselves in a most disturbing fashion in the reader's mind. The apparently straight-line development loops into helices and even into a kind of literary equivalent of the Klein bottle, whose inside is its outside.

Illusion is everywhere. It is now clear that The Book of the New Sun, originally touted as fantasy, is in fact straight science fiction, pure if not simple. The language is the language of fantasy, for in the dying earth which is the novel's setting, technology is ancient and strange, and generates none of the jargon used by those for whom, like us, it is mundane and fresh. Words here are measured, and resonant with an archaic gravity. It takes the reader some little time to realize that the prophesied fountain at the heart of the ancient sun will be what physicists call a "white hole"; that "ships" sail in the electromagnetic winds of space as well as in the sea; that the "Matach in Tower" where the story begins is an ancient spaceship; that the "sailor" Jonas with his metal hand, like Captain Hook's, is not a man of flesh with a metal prosthesis, but a robot with a flesh prosthesis; that the soldiers' "lances" are lasers.

The Sword of the Lictor takes Severian, the banished torturer, along with his lover Dorcas to the city of Thrax, his planned destination though not, as it turns out, his final end. Mysteries abound. Why does Dorcas hate water and vomit up balls of lead? (There is a good clue in the New Testament). Why does Severian's holy relic, the claw of the Conciliator, sometimes perform miracles and sometimes not? Is the Alzabo (a carnivorous monster) purely a beast when it speaks with the tongues of its recent victims? Is the massive, neanderthal Baldanders the slave of courteous, unsleeping Dr. Talos, or vice versa? Beneath the lovely masks of the alien visitors, are the snarling, fanged faces the ultimate truth?

Severian stoically carries out his duties, killing without cruelty, sparing without love, obsessed yet serene. He is perhaps the most extraordinary hero in the history of the heroic epic, and none of his confrontations are without surprises.

The book is marvellously written throughout. Tiny, parenthetic details are often as important as the dramatic set pieces. Careful readers will pick up clues, seldom explained or even emphasized, that reveal a network of strange, half-concealed relationships between characters and between events.

In fact, there are two "Books of the New Sun." Out in the open is the wonderfully vivid and inventive story of a brave and lonely hero; below is the sea of allusion and juxtaposition, metaphors flitting their tails adroitly like fish, images looming and wavering just beyond the point of sharp focus while, almost out of earshot, a pungent debate on ontology, eschatology and the metaphysics of time is taking place.

There is something for almost everyone here except, alas, for the new reader. To read The Sword of the Lictor without having first read The Shadow of the Torturer and The Claw of the Conciliator, the previous two volumes of this continuing novel, would be to drown in its mysterious tides.

Most of the qualities we have come to expect from Elizabeth Lynn are present in The Sardonyx Net (Putnam, $15.95), notably a sensitive rendition of homosexual and even incestuous relationships. She is a liberal propagandist who asks us not to assume that our present sexual priorities are somehow "better" or more "natural" than those which may exist in other societies in other times and places.

In the past, however, Lynn's most successful protagonists have been women. Part of the trouble here is that Dana Ikoro, the hero of this novel, is a man, and a rather one-dimensional man at that.

Starcaptain Ikoro, a drug-runner, is captured and enslaved by Zed Yago, handsome sexual sadist and member of one of the dominant families of the slave-holding planet of Chabad. By the end of this long book the drug- supported slavery system is tottering, and Ikoro is free again and about to be a father.

Traditional space opera, however, emphasizes action; here the center is a rather dubious sociological argument. Although Lynn is at her best evoking the sights, smells and feelings of other cultures, it could be argued that she has merely substituted one set of stereotypes for another. The story of The Sardonyx Net is, in many respects, that of Gone With the Wind (gracious, slave- owning culture is withered by the winds of change)--in short, Romantic Hokum.

Hokum, because the sociology is cobbled together so implausibly. It is difficult to believe that a high-technology society that uses starships would have any practical use for slavery (which is traditionally associated with low-tech cultures) or, if it comes to that, would have an economy based on the export of fur coats. The dressing up of ancient history (feudalism, slave cultures) in futuristic clothes is fast becoming one of the tiredest of science-fiction clich,es.

Lynn's tremulous sensitivity--her alienated characters keep on flinching--also becomes wearing after a while. Faces close like fists and people's stomachs contract in a kind of continuous peristalsis throughout this rather humorless melodrama.

Rudy Rucker, author of Spacetime Donuts (Ace, $2.50), seems to know a thing or two about drug-based cultures as well. His hero is charmingly and convincingly stoned for much of the action, which takes place in a near-future America where the masses are kept docile by watching three-dimensional TV. These are familiar ingredients, and none too promising, but Spacetime Donuts, though lightweight, is thoroughly original for a reason almost unique in science fiction. The author is besotted with mathematics.

In his previous novel, White Light, it was set theory and Cantor's transfinite mathematics. Here it is the geometry of space. It seems that if you can make yourself shrink and keep on shrinking, eventually you find yourself in a universe that's very big rather than very small. The story of how Vernor Maxwell saves America, and blows the mind of its ruling computer by taking it on a metaphysical round trip through space, is a racy and entertaining tale, cheerfully full of bad language and bad taste.

George Alec Effinger's The Wolves of Memory (Putnam, $14.95) is a tragicomedy, also set in a future where earth is run by a computer. Effinger's computer is even nastier and more enigmatic than Rucker's, and both computers leave Stanley Kubrick's Hal looking, comparatively speaking, like a good guy.

The unfortunate hero, Sandor Courane, has been posted to three wholly unsuitable jobs by Tect, earth's electronic ruler, and has failed at all three. He is then sent by matter transmitter, supposedly for rehabilitation, to a desolate planet where a tiny population of similar misfits is trying to scratch a living. All of them eventually contract a disease which always terminates in death, whose first symptoms are intermittent losses of memory.

Their only link with earth is through Tect, who is unhelpful and insulting whenever they ask advice. The story begins with Sandor carrying a nameless corpse through the desert for a reason he cannot remember. Things become clearer as brief flashbacks of memory begin to fill in the picture. Everything centers on the dialogue between well-meaning Sandor and Tect, who is blustering, aggressive, sadistic, autocratic and unctuous by turns. The doomed struggle for survival of the little community is vividly rendered and blackly humorous. Tect's motives remain obscure until his last godlike but surprising gesture.

Effinger steers his story with wry precision along the razor's edge between the grimly depressing and the pointlessly funny. His cool reluctance to tug at the reader's heartstrings becomes, after a while, quite moving in itself. This is a good book.

Readers who have been put off by the austerity of Michael Bishop's science fiction at novel length should try again with Blooded on Arachne (Arkham House, $13.95), his first collection of short stories, which are nothing if not colorful. The stories range from good to excellent.

The exoticism of most science fiction is paradoxically predictable--bizarre aliens based on relatively few earthly models, with the spider, the bee, the octopus and the lizard predominant. What makes Bishop's sense of the exotic so unusual is that he forces us to apprehend it inwardly. He is not so much a teller of traveler's tales as a structural anthropologist, a decoder of alien cultures.

The first two stories are Robinsonades. "Blooded on Arachne" tells of a cadet's rite of passage when deliberately stranded on a desert planet, with only giant spiders for salvation. His feelings about these spiders (and therefore ours) are very far from the reflex disgust such images are normally supposed to produce in the reader. ''Cathadonian Odyssey" (alien man Friday befriends crashlanded lady-scientist Crusoe) hauntingly changes direction, and becomes a science fictional rendition of the old chiller, "The Monkey's Paw."

"The House of Compassionate Sharers" is simply brilliant in its account of a mutilated man, reconstructed from metal and ceramics, coming to terms with his own newly dual nature by being forced to confront the familiar in a genuine alien, and the inhumanity in a genuine human.

"Effigies" and "The White Otters of Childhood" both deal with the violent death spasms of doomed races, imaged in the former in a vegetable love and in the latter in a human surgically altered into a shark. "Leaps of Faith" takes its central metaphor from fleas, whose prodigious acrobatics become emblematic of the mind's leaps away from the unbearable and towards God. None of these complex stories is remotely susceptible to synopsis, and summarized in a sentence must sound merely weird. Weird they are, but implacably almost every story takes a form of alien life as a metaphor for something in ourselves, or something we lack. It is perhaps rather chilling that so few of these creatures are even warm-blooded. They include spiders, fleas, butterflies, tomatos, and even rustling weeds. But one of the strangest and most alien minds of all is the author's own, as described in the autobiographical fantasy "On the Street of the Serpents," where he sees himself as both victim and killer. (An American alien in Spain, he assassinates Mao Tse-Tung.)

In our real lives we are forced, daily, to confront the alien in one form or another. Normally we try to domesticate it by pretending that it is basically just like us. Bishop takes no such easy way out, but what he has to say of alien relationships is the reverse of the escapism that sf is so regularly accused of fostering. This is a fine collection.

There have been recent cries of doom from those who believe that at the outset of the 1980s we are witnessing the death of sf: Spaceships flying out the window as the latter-day clones of Winnie-the-Pooh and Gandalf walk in the door. But if Wolfe's, Effingers, Bishop's and even Rucker's books can be taken as a reasonable sample in just one month, then the Cassandras are wrong. Sf is flourishing as seldom before.y