NEW YORK - Joni Mitchell is terrifying. Yes, behind that sweet fragile voice, those sensitive lyrics, lurks a seductress. From her men she gets inspiration for songs rather than entries in a diary.

And now, on her latest album, "The Hissing of Summer Lawns" (Asylum), she makes her strongest case yet for her uncompromising sensualism and expresses her utter disdain for conventions, whether they be those of the middle class or the conventional non-conformers.

Her position is stated clearly in the first song on the album, "In France They Kiss on Main Street," a paean to her rock-and-roll teens containing a frank challenge: They don't take chances, and they seem so removed from romance. They've been broken in churches and schools and molded to middle-class circumstance."

This Is followed by "The Jungle Line," surely one of the strangest and most compelling songs ever recorded, a Siren's song full of ex­otic images and Africa mixed with modern decadence and all wrapped up in a French painter's vision, presented over a mix of electronic sounds and African drummers.

"Edith and the Kingpin" tells the story of a "small town bit man" who should have no trouble conquering Edith - but they end up in an ominous stand-off.

Passions overflow on the next cut, "Don't Interrupt the Sorrow," a celebration of emotions evoked as "anima rising." The man here con­stantly loses stature as the woman is mythicized through heroic comparisons. The final lines reveal a contempt for the man that is truly terrifying.

"Shades of Scarlet Conquering" perversely praises the fantasizing movie-goer who succumbs to the "Gone-With-the-Wind" maxim: "A woman must have everything."

The title song opens the second side and clearly expresses Mitch­ell's loathing for the convention­al middle-class life. Only a blood red fantasy can keep the wife home in her suburban prison.

Joni Mitchell's image of herself as a loner comes out most clearly in "The Boho Dance," a song that con­trasts the non-conformist life and the conventional life and finds both wanting: "Nothing is capsulized in me, on either side of town. The streets were never really mine, not mine these glamour gowns."

"Harry's House" savagely satirizes the loss of sensual values among the bourgeoisie, interpolating a jazz love song, "Centerpiece " to drive the message home.

The album ends with two songs that try to come to grips with the hedonism that is at the core of Joni Mitchell's approach to love. "Sweet Bird" ponders the passing of time and the lack of lasting companions, while "Shadows and Light" attempts to deal with morality by ignoring it while casting conun­drums in the form of a Gregorian chant.

Joni Mitchell has never been the soft, vulnerable creature she often is mistaken for. With "Hissing of Summer Lawns," she finally dispels all illusions and makes a very provocative and convincing case for the dominance of the pleasure principle.