Robert J. Emry and Hyracotherium Skeleton, by Krantz, Victor, 1985, Smithsonian Archives - History Div, The skeleton of a Hyracotherium, a tiny horse that heralded one of the major evolutionary trends of the age of mammals - the move to grazing - from the National Museum of Natural History's new exhibit "Mammals in the Limelight," opening May 30, 1985. In the background is Robert Emry, Curator of fossil mammals in the Department of Paleobiology, who was in charge of the planning committee for the hall..