BUTTERFIELD 8John O'HaraHarcourt, Brace ($2.50).
The generation that stumbled into a slightly intoxicated maturity in the early 1920's found in F. Scott Fitzgerald a spokesman who dramatized their emotional problems, made articulate their aspirations, and told some excellent stories while doing so. Last week the publication of John O'Hara's second novel made him the strongest candidate among U. S. novelists for the part that Fitzgerald has vacated by growing out of the ranks of the young. A more impressive and ambitious volume than Appointment in Samarra, his first novel, Butter field 8...