This book treats more than 750 families that were firmly established, by the time of the work's original publication in 1912, in the central latitudes of the state. Based on a survey of the contents of the volumes, this region was broadly defined by Cutter as bordering Orleans, Genesee, and Wyoming counties on the west; the New England states on the East; Orange and Putnam counties with the Pennsylvania border on the south; and St. Lawrence and Essex counties on the north. Inevitably, one finds New York families included in the work located outside of this region--notably in Chautauqua and Cattaraugus counties to the west--as well as many families who migrated from New England across the state. Each essay in the copiously illustrated work begins with an explanation of the derivation of the family's surname. Cutter then traces forward from the oldest known ancestor to the principal subject of the essay. This is followed by a detailed biography of that person, often with his photo, as well as an enumeration of collateral lines related to the principal subject. The index at the back of the final volume identifies some 6,000 descendants.