Vineyard artist and writer Margot Datz posits a universe where men, taking a page from Darwin, descended as apes from the trees, whereas women “rose up from the frothy sea, as resplendent as Aphrodite on her scalloped chariot.” But the mating call is more persistent than the tug of a thick rope, so we mermaids have “abandoned our psychic habitat to seek mates on shore, and we have been like fish out of water ever since.” Ain’t that the truth?

The images in this book, of black-enameled bathtubs at the bottom of the sea, of pearl-draped mermaids in Fellini-esque hats seated beside floral china teapots, of hidden jungles where you can smell the frangipani and hear the shrieks of mythological birds, and of glittery gatherings of mermaids in a midnight bay, all of it weaves a mood like the enchantment of waking from a lucid dream.

Landlocked Mermaids is a siren call for women to follow their truest, deepest, most gorgeous impulses. Now, in this post-feminist era, femininity itself can safely be unleashed, protected as it is by women’s own independence. Datz’s mermaids adore mating rituals, but not for a heart-beat do they need them for their economic survival. On a page entitled Ahoy There, Mate, a slinky mermaid with long red tresses is grasped by a black-bearded fisherman wearing thick boots and waders. This ostensibly captured mermaid “bravely enters courtship with her senses alert.” Clearly she is in full command of her faculties on board the ship, whereas the fisherman, should he follow her over the gunwale, would sink hard and fast.

Many of the mermaids are happiest in the company of one another, such as in a conga line of gals of every age and ethnicity celebrating Great Aunt Tallulah’s birthday under a Caribbean moon. And then there are the occasions when solitude exerts its own tidal pull. Over the caption There’s Nothing Sadder Than a Broken-Hearted Mermaid, a bare-topped sea lady sprawls over a pink divan below a stateroom window facing a wine-dark sea. But in a happier solitary moment entitled Dawn, a mermaid with long carrot tresses and waist-deep in twinkling waters, holds up a necklace of seashells opposite a page that declares To Thine Own Mermaid Be True.

So many clever touches adorn this book that it could take years to discover them all — Landlocked Mermaids was definitely designed for repeated perusals. On one page bearing the caption Marlaina Walks Her Dog, a black-hatted mermaid holds a black parasol under a gibbous moon. She wears elbow-length black gloves and a black, lacy, bejeweled capelet as she escorts a tiny merdog with a pearl collar and a bow around a tuft of silver hair. This hilarious creature is the spitting image (apart from the mer-tail) of Datz’s own pet dog, a Chinese Crested named Yoda, its illustrated form reprised under the artist/author’s photo on the last page.

Landlocked Mermaids is a book that will probably be bought in bulk — the typical customer might start with one for herself then, with a shrug, pick up another for her mom, another for her soul mate of an accountant, and finally, four more for her circle of best friends. It might be hard for her — or any of us — to articulate quite what it all means, but she’ll grasp the underlying message: go forth, be beautiful, be free.

THE BEACH HOUSE by Jane Green, Viking, $24.95.

Although Ms. Green lives in Connecticut, she has clearly spent time on Nantucket, more than enough to bring verisimilitude to this mainstream romance about summer people on that Other Island.

Sixty-five year-old Nan has a waterfront house in Siasconset – the kind of lovable but dilapidated old mega-cottage that some of us have enjoyed in our family memories, the rest of us wish we’d enjoyed in our family memories, and that evil developers would swindle their own families to acquire and tear down. Now Nan’s once-resolute trust funds seem to be shorting out, so she decides to rent rooms for the summer, gathering around her a select crew of the lost and broken hearted. Oh, and at least one evil developer.

Ms. Green has written nine previous novels, most of them making it onto the New York Times best seller lists. In 2007 she won the Cosmopolitan Fun Fearless Fiction Award. The Beach House is not so much fun in the Sex-and-the-City-let’s-see-how-many-pairs-of-Manolos-I-can-pack-into-a-suitcase mode; it’s more of an honest exploration of the forces that drive people apart and then, with any luck, together.

In The Beach House we meet a woman who has dumped her husband for cheating and yet whose teen daughter, the imbecilic ingrate, sides with the dad. There’s a couple who love each other dearly and would go on living happily ever after were not the husband beginning to twig to the fact that he’s gay. And then there’s Nan’s grown son, Michael, Manhattan designer of jewelry and serial romantic. Michael falls for his lady boss who is so wrong for him and he for her, yet neither of them can see through the fog of their own misguided carnality. All of this will be sorted out under Nan’s wise woman t.l.c. and the Nantucket sun’s healing rays (once the morning fog burns off).

Every year one of the big designer authors appropriates the name “Beach House.” A couple of summers back it was James Patterson, before that Mary Alice Monroe. A visit to Amazon.com spews up some 17,000 hits for the title. Soon the big publishers will hold a lottery to see who gets to use “Beach House” next. I’m rooting for Alan Dershowitz.

Jane Green’s entry into the field is certain to fly off Vineyard bookshelves, here where the life style and scenery are so similar to Nantucket’s. The impoverished aristocrat Nan could just as easily be renting out rooms in West Chop, and her tenants, among the huddled masses of stressed-out metrosexuals, could just as surely wash up here. The Beach House is a beach read par excellence, just the book to transport you through an afternoon on the sand, through several dips in the sea, and five or six applications of sun block. You might even race home to finish it back at the beach house. Or the Walk to the Beach house. Or the Only Two-and-a-Half Miles to the Beach house.

Edgartown Books hosts Jane Green signing copies of The Beach House on Sunday, June 29, at 3 p.m. and Margot Datz Saturday, July 5, at 11a.m.