``All the reasons that a writer shouldn't rush too quickly into print are on display in this collection,'' novelist Jane Smiley's introduction dauntingly informs us. Indeed, Tennessee Williams would probably cringe at the inclusion of ``The Vengeance of Nicrotis,'' which begins, ``Hushed were the streets of many peopled Thebes'' and carries on for 13 overwrought pages. Happily, most of the stories are considerably better. Some, like F. Scott Fitzgerald's ``Babes in the Woods'' and John Updike's ``Friends from Philadelphia,'' address characteristic themes that would be handled with more maturity later. Others are genuine masterpieces- -but it helps if, like Isaac Bashevis Singer, you wait until you're 49 to publish ``Gimpel the Fool.'' Margaret Atwood, Mark Helprin, David Leavitt, and Smiley herself are among the living authors who have bravely allowed their early work to see the light of day here; those who may or may not be spinning in their graves include Henry Miller, Graham Greene, and E.M. Forster. Kiernan and Moore are senior editors at the Book-of-the-Month Club.