The Department of Invertebrate Zoology (IZ) is one of the oldest scientific units in the Smithsonian Institution. It was established in 1856 to house invertebrates collected from the U.S. North Pacific Exploring Expedition. Collections from the U.S. Exploring Expedition (aka Wilkes Expedition) were added in 1858. Current holdings are approximately 35 million specimens in over 15 linear miles of storage. More than 40% of these specimens have computer records that can be queried at the IZ collections database. Parasitic worms (Acanthocephala, Cestoda, Monogenea, parasitic Nematoda, and Trematoda) are now managed by IZ. Brachiopoda and Foraminifera are managed by the Department of Paleobiology; and the Insecta, Myriapoda, and non-marine Chelicerata are managed by the Department of Entomology.