TOLKIEN: A Biography, by Humphrey Carpenter (Houghton Mifflin, $10). Externally, the creator of the hobbits had an uneventful life: orphaned at 12, he served in World War I, spent most of a half-century at Oxford, where he became professor of Anglo-Saxon and an outstanding authority on the West Midland dialect of Middle English and edited and translated the great medieval romance of Sir Gawain and the Green Knight. He also wrote a few books of fantasy in which adventure is cunningly blended with imaginary linguistics, and which became, against heavy odds, international best-sellers. The handling of such a life to make it readable requires special skills which Carpenter employs with notable success.

THE SILMARILLION, by J.R.R. Tolkien; edited by Christopher Tolkien (Houghton Mifflin, $10.95). This long-awaited posthumous publication is a mixed bag: a fine creation myth, an epic struggle between elves and a wicked demigod, the story of an islaands that seems to be Atlantis and a lot of dry, scholarly writing on elvish history and linguistics. The quality is uneven; some of the dry spells are very long, there are no hobbits in the book and (despite scrupulous editing) the various parts of the sprawling material do not always fit together smoothly. But at its best, this volume contains a striking vision presented in superb style.

THE HOBBIT, Or There and Back Again, by J.R.R. Tolkien, with illustrations from the film by Arthur Rankin Jr. and Jules Bass (Abrams, $35). The making of a film from a well-loved novel is even more of a risk in fantasy than in realistic fiction. Each reader carries his private vision from the book, which may or may not coincide with what is flashed on the large screen. In this case, the moviemakers had to satisfy in detail a massive variety of unarticulated views on what Bilbo and Gandalf and Balin really look like, while remaining true to their own private vision. The result, almost inevitably, recalls Walt Disney and it is safe to predict that it will meet with mixed reactions. But there can be no question, at least, that this deluxe edition is superbly designed and that the 230-plus illustrations are most meticulously reproduced.