In 1856, American paleontologist Joseph Leidy (1823–1891), professor of anatomy at the University of Pennsylvania, accurately identified several fossil bones as being those of dinosaurs. These fossil remains were among the first to be collected in the western United States by an official geological survey team in 1855. The bones were found in what is now Montana. The remains were mostly fossil teeth and were subsequently shown to be from Trachodon and Deinodon dinosaurs.