1939 - 1991
Not long after the Hall of Dinosaurs, newly separate from other fossil reptiles, fishes, and amphibians, opened in 1927, plans were afoot to separate the dinosaur exhibits into two halls (1, 1929, p. 2). The new Jurassic Hall was part of a newly constructed building called the African Wing (1, 1934, p. 27) and was to occupy space on the fourth floor around the corner from the original Dinosaur Hall, which would be reformed as the Cretaceous Hall (later known as the Tyrannosaur Hall and then Hall of Late Dinosaurs). The Hall of Early Dinosaurs was named the Jurassic Hall when it opened in 1939. It was generally referred to as the Brontosaur Hall in the 1950's and as the Hall of Early Dinosaurs from the 1960's onward.
The dominant feature of the hall was the Brontosaurus skeleton in the center. The Hall also featured mounts of Allosaurus and Stegosaurus skeletons. The more ancient reptiles, including Diadectes, Naosaurus, Edaphosaurus, Dimetrodon, Dicynodon, Moschops, Scutosaurus, and Eryops were displayed toward the end of the hall (3, 1939, p. 4; 1950/51 8, p. 41;). Other exhibits included eight skeletons of a newly-discovered type of Camptosaurid dinosaur, a free mounted skeletal cast of Placodus, a Nodosauroid skeleton, an unmounted Barosaurus skeleton, and dinosaur tracks from Glenrose, Texas (9, 1938, p. 2, 8). By the 1950's the hall's exhibits also included Hypsonathus, phytosaurs, pelycosaurs, Plateosaurus, Coelophysis, Cotylorhynchus, and Placodus (3, 1953, p. 56-59).
In the 1990's, the Museum's Department of Paleontology reimagined the fossils halls. The Halls of Early and Late Dinosaurs closed to make way for the Halls of Saurischian and Ornithischian Dinosaurs, which are arranged not by chronology but by evolutionary relationships. Many of the fossils in the Hall of Early and Late Dinosaurs moved to the newly arranged halls. Notably, the Brontosaur, by this time called Apatosaurus, and the Allosaurus moved to the Hall of Saurischian Dinosaurs, and the Stegosaurus moved to the Hall of Ornithischian Dinosaurs. In 1993, a special exhibition, Work in Progress: Drawing Board to Dinosaurs was on view in Gallery 77 for visitors to preview the new halls (4, 1993, p. 15).
Content negotiation supports the following types: