Geological Survey Program

fact sheet

Missouri Geological Survey

Director: Carey Bridges, RG

First Dinosaur Bones Discovered in Missouri

In 1942, Daniel R. Stewart, a geologist with the department’s Missouri Geological Survey and graduate of Missouri School of Mines and

Dan Stewart, MGS geologist. Circa 1940s.
Dan Stewart, a geologist with Missouri Geological Survey. Photo courtesy Christopher Wiseman, curator, Joplin Museum Complex.

Metallurgy (now Missouri University of Science and Technology), both in Rolla, was researching clay deposits in Bollinger County near the town of Glen Allen, approximately 35 miles west of Cape Girardeau. While examining an outcrop of clay in a creek bank, a young boy named Ole Chronister poked his head over the top of the bank and asked what Stewart was doing. 

Hypsibema missouriensis, state dinosau,r image
Parrosaurus missouriensis is a hadrosaur – a plant-eating duck-billed dinosaur having more than 1,000 teeth.

When Chronister learned Stewart was researching clay in the area, he told Stewart there was clay on his family’s property and he invited Stewart to investigate. On-site, Stewart observed several neatly stacked bones the family had found while digging a well they later abandoned because sufficient water was not found. Stewart recognized them as being dinosaur bones, and he found more bones 9 feet below the surface. The were embedded in clay inside the well (where the other bones were found), marking the first known discovery of dinosaur remains in Missouri. 

Mrs. Chronister gave the bones to Stewart so they could be examined by paleontologists. The vertebrae bones eventually were identified as belonging to a hadrosaur – a plant-eating duck-billed dinosaur having more than 1,000 teeth. Mrs. Chronister sold most of the bones to the U.S. National Museum, which later became the Smithsonian Institution. Named Hypsibema missouriensis, it became Missouri’s official state dinosaur in 2004, two years before Stewart’s death. In 2022, the State Legislature renamed it Parrosaurus missouriensis.

In 2016, members of the Stewart and Chronister families were honored by the department and the Bollinger County Museum of Natural History during a ceremony held at the Bollinger County Museum of Natural History.

See reproductions of the state dinosaur’s bones and a small model of the dinosaur at the department’s Ed Clark Museum of Missouri Geology.

On Nov. 22, 2021, Sainte Genevieve Museum Learning Center curator Guy Darrough formally announced the discovery of an adult Parrosaurus missouriensis fossil at the Chronister site. Darrough, director of the dig site, said the fossil and its surrounding material weighed 2,500 pounds. The dinosaur was excavated by a team including Dr. Pete Makovicky of the University of Minnesota and Akiko Shinya of the Field Museum. The specimen was transported to the Field Museum in Chicago where it will be cleaned, studied and eventually displayed. Visit the Learning Center where you can see a large model of the dinosaur and others, and visit their lab where you can view scientific studies being conducted on dinosaur bones and real fossils.


11 Missouri dinosaur bones, Hypsibema missourinesis, Smithsonian photo 1
These vertebrae bones, found on Lula Chronister’s property in 1942 made history. They were the first dinosaur bones to be identified in Missouri. They are the bones of a hadrosaur that was later named Hypsibema missouriensis, and renamed Parrosaurus missouriensis in 2022. Photo courtesy Smithsonian Institution.
11 Missouri dinosaur bones, Hypsibema missourinesis, Smithsonian photo 1
The dinosaur bones found in Missouri made their way to the Smithsonian Institution where they reside to this day. The species became Missouri’s state dinosaur in 2004. Photo courtesy Smithsonian Institution.

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