Fossil Amphibians Collection The Field Museum's collection of fossil amphibians and reptiles comprises 5,825 catalogued specimens. The collection is concentrated in the North American Paleozoic, especially the Early Permian. Particularly important holdings are enumerated below. Systematic Coverage-Most major groups of Paleozoic amphibians and reptiles are represented in the collections, notably those from the Early Permian and Late Mississippian. Other groups with significant representation include turtles from the Tertiary, Triassic marine reptiles, Cretaceous dinosaurs and Tertiary birds. Geographic Strengths-Geographic Strengths-The collections' primary strength is North American material, especially Early Permian of Texas and Oklahoma, Late Mississippian of Iowa and Middle Triassic of Nevada. Type Specimens-The collection includes 146 holotypes and 471 paratypes. Early Permian-The core of our Early Permian holdings is represented by the Walker Museum collection, which was transferred here from the University of Chicago. It and our other Early Permian collections come mostly from Texas and Oklahoma, with some important specimens from New Mexico. This part of the collection represents the research efforts over nearly 100 years of some of the best known workers in early tetrapod systematics, including A. S. Romer, Everett Olson, and their numerous students. It is relatively well studied and rich in type and figured specimens. Major additions to our Early Permian holdings within the last 20 years are primarily from Oklahoma, and due to the work of both Everett Olson (then at the University of Chicago) and some of his students, and J. Bolt (as a student at the University of Chicago, and later as a curator at Field Museum). Bolt's activities in particular have resulted in addition of many exquisitely preserved specimens of small tetrapods from a fissure-fill system in southwest Oklahoma. Fossil Turtles-Fossil turtles, most collected from the Tertiary of Wyoming are a significant area of the collection, and largely due to the work of Rainer Zangerl. Dinosaurs-The dinosaur collection includes mostly Cretaceous specimens (tyrannosaurids, hadrosaurs, ceratopsians) from both the United States west and Canada (the well-known mounts of Albertasaurus and Lambeosaurus). The most important Jurassic dinosaur material is a (composite) mounted specimen of Apatosaurus, currently on display in "DNA to Dinosaurs," and the holotype of Brachiosaurus on display in Stanley Field Hall. Recent additions of therapod material includes Cryolophosaurus, a Jurassic dinosaur recently discovered in Antarctica by Research Associate Bill Hammer. Ongoing work in Madagascar by Research Associates Dave Krause and Cathy Forster, Field Museum's G. Buckley, Malagasy and other colleagues is yielding new material of dinosaurs, birds, crocodiles and other reptiles. Marine Middle Triassic Reptiles-O. Rieppel's ongoing field program in the Middle Triassic marine deposits of northwestern Nevada have resulted in significant discoveries of marine Middle Triassic reptiles. Specimens collected represent the only Triassic stem-group Sauropterygia known from the New World (other than the enigmatic genus Corosaurus from Wyoming). Mississippian Amphibians-A remarkable assemblage of Mississipian amphibian material was collected within the last 10 years by crews directed by J. Bolt, all from a single locality in southwestern Iowa. This site, a sinkhole some 16 meters in diameter, was probably a pond during the Later Mississippian. It has produced hundreds of tetrapod specimens; many are very well preserved and some are nearly complete. This locality was the first reported occurrence in midcontinental North America of Mississippian tetrapods (the continent's oldest), and is one of no more than two dozen such localities in the world. Other Geology Department Collections: Paleontology | Fossil Amphibians and Reptiles |Fossil Fishes | Fossil Invertebrates |Fossil Mammals | Fossil Plants | Physical Geology