MINI MAY be the fashion in women's skirts this fall, but the prevailing trend in children's picture books is decidedly maxi: lots of outsize formats, lavish illustration and, in some instances, conceptions so sophisticated and grandly executed as to raise questions about what audience the illustrator is intending to reach.

An elaborate neo-Victorian picture album is Heidi Holder's Crows: An Old Rhyme (Farrar, Straus and Giroux, $15.95; all ages). Its starting point is a three-verse rhyme about various folk superstitions connected with the sighting of crows (i.e. "One is for bad news/ Two is for mirth/ Three is a wedding/ Four is a birth"). But it is no more a counting book than the illuminated manuscript Les Tres Riches Heures du Duc de Berry is a calendar. The meat of the work is 12 meticulously painted scenes from the lives of a lady mink and a gentleman weasel, each one depicting the happening predicted on its adjoining page. Holder's unlikely hero and heroine are rendered with remarkable verisimilitude -- not a whit of prettifying or sentimentalizing of these wild creatures. Yet the artist believably outfits the duo in costumes of rich, almost Elizabethan splendor. The mink's gowns of silk, satin and taffeta are almost palpable. Holder captures the mood of each event in her colors (pale blue and brown for bad news, glowing peach and pink for mirth, etc.), and her wondrous decorative borders for each scene attest to her interest in Tarot cards, the symbolism of flowers and other omens of good fortune and bad. The work is an awesome labor of love, a triumph of painterly illustration that rewards many a re-viewing. This said, it will be best appreciated by adult picture-book aficionados and susceptible older children.

Graeme Base's Animalia (Abrams, $14.95; all ages) is a family entertainment of an alphabet book. Its full- and double-paged animal paintings A to Z -- more comic/grotesque than beauteous -- are crammed with letter objects of obvious and abstruse varieties. The "Crimson Cats" pictured conceal a concertina, chandelier, cola can, conch shell and cork, among countless other objects both easy and hard to find. With the paintings' layers upon layers of revelation, there's no reason to doubt the Australian illustrator's estimate of more than a thousand hidden objects, including a concealed picture of the artist himself on almost every page. And considering the obsessive quality of the art work, the three years it took to complete is also understandable. It's an alphabet for a rainy day's diversion.

In Lenny Hort's retelling of The Boy Who Held Back the Sea (Dial, $15; ages 10-up), the accomplished painter Thomas Locker takes on the traditional tale of the brave lad who keeps his finger in the dike all night, thereby saving his town from flooding. More painter than illustrator, Locker is intent on giving his audience an authentic sampling of 17th-century Dutch landscape and genre painting. The spirits of Vermeer, Rembrandt and others hover over these stately pictures. But Locker's commemorative art allows the young hero only the smallest place in each picture. The child listener is left to imagine what the hero looks like and exactly what a hole in the dike is. Locker's paintings are like scenic backdrops, adding almost nothing to the narrative dimension of the tale. Perhaps if Hort's retelling were more direct and forceful, the lack of support from the pictures would have been less obvious. Locker's art work was more effective in those earlier books where he tailored his own texts to carry the listener into his paintings. As an introduction to Dutch art, however, it's a pretty nifty nursery coffee-table book.

Art and words march in perfect synchrony in William Steig's The Zabajaba Jungle (Michael di Capua Books/Farrar, Straus and Giroux, $13.95; ages 3-up), a work as likely to mesmerize a great many young listeners and viewers as it is to perplex adult readers. With no preliminaries, Steig hurtles us into his young hero's dream of glory: "Leonard is slashing at the vines and creepers with his sharp bolo. He is fighting his way into the Zabajaba Jungle, where, it is said, no human being has ever penetrated." Are we hooked? You bet. There we are, beside stalwart, fearless Leonard at the cutting edge of danger. And danger we get: carnivorous plants; writhing snakes; hostile mandrills "with blue behinds," and a dark journey into the gaping mouth of a petrified monster and eventually out "through the great cloaca." As always, Steig's stately language is a joy to the ear: "Squawking birds and raucous insects fly about"; "His fall is broken by tiers of fern fronds." No baby talk here. Events there are aplenty, with Leonard the winner nearly every time. And at the end of it all, there is a mind-boggling image of Leonard encountering his parents who are encased in an enormous glass bottle. They are oblivious to their son and his recent perils until he smashes a hole in the bottle. What a commentary on the inner lives of children and the limits of adult understanding! Full of positive vibrations, this mysterious work derives its power from satisfying two urgent childhood longings: for adventure, and for some bolstering of a sense of personal competence.

An impressive performance in quite another vein is illustrator Peter Spier's We the People: The Constitution of the United States of America (Doubleday, $13.95; ages 3-up). Concentrating on the 52-word preamble, Spier takes it, phrase by ringing phrase, and manages to breathe pictorial life into its largely abstract terminology (particularly for a young child). The artist uses a generous format to provide an energetic barrage of small watercolor vignettes, allotting as many as four pages to a phrase. For "We the people of the United States" the viewer sees an auto mechanic, computer operator, eskimo, lumber jacks, Hassids, street people and surfers among 43 portraits of citizens then and now. Forty pointed images elucidate "promote the general Welfare." The sum total is an exhilarating visual appreciation of the document and of its living meaning. Bonuses include a copy of the full Constitution, an endpaper facsimile of its original appearance, a bit of background history and contemporary portraits of all 38 signers. An admirable, low-key 200th birthday salute.

Chris Conover's The Adventures of Simple Simon (Farrar, Straus and Giroux, $13.95; ages 3-up) is anything but simple. That its hero is actually pumpkin-headed is droll and appropriate enough, but when "the fair" Simon is heading toward turns out to be a world-wide jamboree with an international cast of animals including camels, penguins, Bengal tigers, kangaroos and more, the visual goings-on begin to upstage Simon's nursery-rhyme shenanigans. Foremost among the scene stealers are the talented Conover's wondrous assortment of bears -- panda, polar, brown and a koala -- all gloriously costumed. Add to this cameo roles by characters from 16 other nursery rhymes, and you have the picture-book equivalent of a six-ring circus. The eye is overstimulated, and the narrative thread is all but lost.

WITH FLUID, almost musical illustration, Errol Le Cain stages a magnificent production of Growltiger's Last Stand and Other Poems (Farrar Straus/Harcourt Brace, $12.95; ages 3-up). Three well-chosen selections for young listeners from T. S. Eliot's Old Possum's Book of Practical Cats compose, in Le Cain's sure hand, the nursery set's equivalent to Broadway's long-running Cats, taken from the same source. In the title poem, the artist outfits the reprobate black cat, "The Terror of the Thames," in red bandana, sash and boots to match his single, fiercely glowing red eye. The sinuous and sleek army of blue-eyed siamese who sneak up in sampans and junks to take vengeance are made all the more comically sinister by the wonderful burnished gold conical helmets they wear right down to their eyeballs. The final picture of Growltiger walking the plank is etched into a great golden gong, presumably commissioned for the day of celebration that "was commanded in Bankok." Le Cain's absolute command of the page space, his flair for the most memorable angle of presentation of the characters in action -- for instance, his Great Rumpuscat arising from a basement stairwell, his eyes "like fireballs fearfully blazing" -- give to Eliot's antic words the maximum dramatic enforement. In "The Song of the Jellicles," Le Cain's small black and white cats, as natty as penguins, "wait for the Jellicle Moon to rise." It has, of course, a definitely Jellicle face. Every detail of furnishing -- even the drawing-room window which has a bit of Jellicle stained glass -- enhances the madcap rhyme. For all the richness of his illustration, there is never a sense of too much. It deserves to be a smash hit in the picture-book world.

An instance in which stark art and simple story are perfectly mated is Tejima's Fox's Dream (Philomel, $13.95; ages 3-up). This Japanese artist's bold, multicolored woodcuts are particularly well suited to the tale of a lone fox out hunting on a cold, snowy night. The book's large, vertical format invites the viewer into the wooded landscape with its strong images of snow-laden trees against black sky and blue-white ground. Nothing much happens. The fox gives chase to a snow hare and loses its trail. He and we are caught up in the suggestive patterns of snow and ice against the dark tree limbs. The fox dreams of the warmth of spring and remembers his mother and siblings. We feel the cold and his solitude, and we exult when he sees a vixen in the distance and runs to nuzzle her. Spring, like morning, will come again. A peaceful, reassuring bedtime story, restful to eye and ear.

A generous horizontal format, with traditional black- and colored-ink drawings by Suekichi Akaba -- all reproduced on a heavy rice-grained tan paper, beckons us into Momoke Ishii's spirited retelling of a Japanese folk tale, The Tongue-cut Sparrow (Lodestar/Dutton, $13.95; ages 6-up). At the climax of a suspensefully drawn-out story, an ill-tempered and greedy woman gets a forebearing comeuppance from the sparrow whose tongue she has spitefully snipped. Katherine Paterson's translation retains a decided Japanese flavor, even to keeping a few well-chosen Japanese phrases. (These are translated in a simple glossary at the book's end.)

An ambitious American artist-historian, Deborah Nourse Lattimore, tries to tell a Mexican tale based on Aztec mythology by using elements of authentic Aztec illustration, in The Flame of Peace: A Tale of the Aztecs (Harper & Row, $12.95; ages 5-8). Digesting a complicated quest tale about the young hero Two Flint's mission to battle nine evil demons in order to bring from the hands of Lord Morning Star a new Fire of Peace to his beleaguered capital city Tenochtitlan is not exactly made simpler by having to master as well a nervously rococo and highly stylized pictorial vocabulary. Children who enjoy decoding messages will best rise to the challenge. Reading the pictures is definitely like mastering a difficult visual shorthand. The endpapers provide a helpful glossary of images, but putting it all together will take much time and effort. Not for every child.

It is Catherine Brighton's engaging full-page watercolor paintings of a Renaissance household that give Five Secrets in a Box (Dutton, $11.95; ages 3-up) its chief charm and content. With high seriousness and loving attention to pictorial details of fabrics, furniture, architecture, patterned floors and stone staircases, she makes a largely successful sttempt to recreate the 16th century house in Pisa, belonging to the astronomer Galileo. Everything we see is through the eyes of Galileo's small daughter, Virginia, who rummages about everywhere, most particularly examining the contents of a brass box on her father's desk. (Galileo catches up on sleep by day, since he starwatches at night). What plot there is focuses on the box's contents: two magnifying lenses, which Virginia uses as a primitive telescope; two other lenses that tint what she sees through the telescope; and, finally, a feather. When Galileo awakens he informs her that the feather is important to his work. But neither Virginia nor the reader will learn any more. A child sufficiently piqued will have to head for the nearest adult. There is a disparity between the solidity and charm of the pictures and the insubstantiality of the text.

Stacey Schuett's low-key twilight-lit full-page paintings for Lights Around the Palm (Knopf, $12.95; ages 3-up) provide just the right amount of real-world ballast for Mavis Jukes' slight but winning tale of make-believe. Emma, a dreamy 7-year-old, chats with the farm animals and is teaching Highpockets, the horse, to read from her alphabet book. (Doesn't he reply with a loud "N-eight" each time she shows him an A?) Kindergarteners to second-graders will enjoy Emma's carefully contrived dialogues with cat, dog, hen and sheep. Best of all, the author catches the friendly banter of family give and take. Eventually even Emma's hard-hearted brother comes round to backing her latest flight of fancy: decking out the backyard palm tree like a Christmas Maypole. Artist Schuett wisely lets each of us imagine that on our own. The paintings have a fresh Western look, appropriate to the California locale.

In The Idle Bear by Robert Ingpen (Bedrick/Blackie, $ . ; ages ), Australia's winner of the 1986 Hans Christian Andersen Medal, gives us two irresistible teddy bear ancients (50 years old at the least) who carry on an existential conversation. Ted, the larger and more bumptious of the duo, wears a blue-striped shirt and is given to such pronouncements as "When I was young, I used to have a lot to do. I was as important as a bear can be." Teddy, in red-striped sweater is the more sweet-natured and reflective, always pinning Ted's generalizations down. They have their battle scars: Teddy leaks straw and has a worn-out growl. Ted sports a bandage on one paw and can growl feebly only if he stands on his head. They discuss where teddy bears come from and what it means to be a worldly bear. Teddy's owner, we learn on the last page, "is an Idle," thus accounting for book's title and Teddy's legitimate claim to the family name. Ted is too proud to ask what an Idle is. There is not much "plot": the pictures alter just enough to make the bears seem animate; the dialogue is out of Samuel Beckett, but as mesmerizing as listening to two toddlers in a sandbox. Teddy bear lovers of all ages will find cause to smile, and the 12 full-page candid portraits of the bears are masterly.

Selma G. Lanes' books include "The Art of Maurice Sendak," "Down the Rabbit Hole," and "An Actor's Life for Me!," published this month.