Paleontology and Comparative Anatomy Exhibit in the South-East Range of USNM, by Unknown, c. 1881-1887, Smithsonian Archives - History Div, The Paleontology and Comparative Anatomy Exhibit in the South-East Range of the United States National Museum, now the Arts and Industries Building, c. 1881-1887, has large mammal skeletons including a giant sloth (Megatherium) and a mastodon in the foreground, and behind exhibit cases. Marine mammal skeletons are suspended from the ceiling..