Dozois' second stab at editing this series concentrates on magazine pieces rather than work previously published in hardback. There are a few excellent stories among the present eight, notably Theodore Sturgeon's ""Harry's Note,"" in which an invisible extraterrestrial regretfully identifies a dead end in the evolution of Homo sapiens, and George R. R. Martin's deftly turned ""Bitterblooms,"" in which a young girl is sheltered by a lonely would-be-enchantress against the rigors of a harsh and dangerous planet. But there are also several disappointments. ""The Screwfly Solution,"" by ""Raccoona"" (Alice) Sheldon, has a splendid premise about a horrific alien experiment in human population control, but the story itself is couched in a more trivial mode than Sheldon's work as ""James Tiptree, Jr."" In a long and overweening collage, Steven Utley and Howard Waldrop--authors of the analogous but much better ""Custer's Last Jump""--crank up Frankenstein's monster for further adventures in a subterranean polar realm. Edward Bryant has a lively, uneven go at interweaving an epidemic of supernovas with the story of a middle-aged man's bout with prostatic cancer. Spider and Jeanne Robinson get bathetically carried away with a very good idea about free-fall dancing. Michael Bishop and John Varley just miss their best form. An agreeable anthology, but more notable for good intentions than lofty achievements.