Back in the Thirties, Dorothy L. Sayers and her friends, including heraldry-expert Scott-Giles, cooked up spoof ancestors for her fictional sleuth, Lord Peter Wimsey. This tiny book, largely based on Sayers/Scott-Giles correspondence, is therefore a double-whammy of whimsy: the mildest sort of amusement imaginable, as Scott-Giles traces the Wimsey line, with its two strains--doltishly lusty and cleverly cool--from Normandy to English barons, earls, and dukes. Included are a ""Songe for Voyce and Lute"" by Roger Wimsey (""Fy on thee, fy""), quotes from Horace Walpole on the Wimsey clan (""With them it is god or clod""), and recurring references to the Wimsey escutcheon--with its domestic cat and running mice. A half-dozen chuckles, a score of smiles, but mostly the bland leftovers of an in-joke that probably should never have been let out. Still--a surefire Christmas-stocking doo-dad for Lord Peter's ever-faithful valets.