Ornithologist of the U. S. National Museum, famous for his book, Color standards and Color Nomenclature and the series of many volumes entitled, The Birds of North and Middle America. These letters were written to Witmer Stone and covered a wide field of special aspects of ornithology, including identifications, loans, exchanges, techniques and preservation of type specimens, and books needed for his color charts. Personalities in the bird world, visiting ornithologists and biographical notes conclude the subject matter.