This milestone anthology issue appropriately leads off with an excerpt from Charles Olson's Ezra Pound ""Files."" New Directions, Pound's publisher and early shill, continues its dogged scan for pacesetters in ""the experimental arts."" Among the poets, playwrights and fiction writers: Gilbert Sorrentino, Coleman Dowell, James Purdy, Tennessee Williams, etc.; and there's a more extensive presentation of German ""Functional Poetry."" All 29 earlier issues in the series may be obtained from J. B. Lippincott. Catalogue available.