Sparse on names and fairly mild, this 29th annual collection. All are from the mystery magazines--except for Gerald Green's hortatory joke about the advantages of putting criminals on salary (Playboy) and Edith Taylor's sinister twist to Nancy Drew detection (from Killers of the Mind, the 1974 M.W.A. annual). There are psycho/horror studies: Jerry Jacobson's reading of a teenage poet becomes the ""voice"" of her dead sister; Stanley Cohen's chiller about a Calley-like sniper working on a ski lift; and Lawrence Block's deceptively gentle commiseration with an animal lover avenging a dead lamb. Also among these 25 diversions: a Holmes invention by R. R. Irvine; an amiable appearance of Miss Phipps by Phyllis Bentley; and a turnabout heist caper by Francis Clifford. Not many surprises and not much wallop, but it passes the time.