Two novellas, very dour and summarizing, about the hapless and increasingly compromised German generation between the wars. In ""The Spider's Web,"" Theodor Lohse is an almost invisibly mediocre young man who plays that very facelessness into the grand opportunity for such nonentities that fascism always is. Roth's portraiture of Nazi amorality lends support to Hannah Arendt's ""banality of evil"" idea, but the book is artificially dramatic, breathless with journalistic hammer blows. More interesting is a look at the German film industry between Versailles and Potsdam, ""Zipper and His Father."" Zipper is also, like Lohse, a failure, as is his father; but he marries a lesbian actress, Erna, and, if nothing else, is put into vague proximity of some success in life. Chiefly for its paragraphs about the flimsy feverishness of the film ""industry"" at the time, this short novel catches. Still, both stories here are minor Roth--punishingly gray and anxious to make their points.