Were You Born for Each Other?

In his eighth book, psychologist and frequent TV talk-show guest Leman recycles material from The Birth Order Book et al. to advise readers on romantic relationships. Unremittingly arch and playful, he maintains that successful mating depends on choosing a man or woman whose birth order in the ``family zoo'' is different from one's own. The cosseted baby, for example, should avoid marriage to another Last Born, since both require the strong control of a determined First Born. There are many variables, such as the effects of gender among siblings and the spectrum of potential difficulties surrounding the Only Child. About Middle Borns, so various in character, Leman notes that predicting their qualities as romantic partners is akin to ``nailing gelatin to a board.'' Literary Guild and D o ubleday Book Club alternates; auth o r tour. (Feb.)