Under that perfumed title: the sexual concerns of various ages arranged and discussed chronologically (The Sensual Seedling, The Budding Bough, etc.). ""Sometimes it is only through such hindsights that we can understand why some of us have always thought of sex as something shameful while others celebrate the joys of the flesh,"" burbles Olds conventionally. As she acknowledges, Olds tops even Mary S. Calderone in recommending that parents ""openly encourage their children to masturbate."" Adolescents, however, should refrain from intercourse until they're emotinally mature--better masturbation, petting to orgasm, or oral sex (as a means also of avoiding unwanted pregnancies, and reducing the risk of sexual disease). Among young adults, Olds takes particular note of sexual disease as a damper; of work involvements and waiting, and cohabitation (no guarantee of successful marriage). Pregnancy may bring problems (some men are turned off, some turned on); parenthood almost inevitably crimps sexual relationships: extramarital affairs can be ""healthy"" or ""disturbed"" (according to Dr. Albert Ellis) but they rarely break up marriages (according to a Playboy survey). There's more, considerably more, about extramarital affairs at midlife--with due note, as well, of women's declining ""body image."" What all this is getting at--a kind of pragmatic hedonism--is best represented by the troubled couple Olds introduces at the outset: the husband gives up his longtime extramarital lover; the wife joins a swingers' club with him. The sociology is better tapped at Olds' sources; a standard sex guide will serve better for negotiating rough passages.