Cyrus Thomas and the Southern Illinois University Museum

Cyrus Thomas during the Hayden Geological Survey of the Territories, 1870
Cyrus Thomas during the Hayden Geological Survey of the Territories, 1870, from the USGS Denver Library Photographic Collection

Born in Tennessee in 1825, Cyrus Thomas began his eclectic career studying law and moving to Illinois in 1849, where he practiced in Murphysboro from 1851 to 1864. He married John A. Logan’s sister Dorothy Adeline Logan in 1853. After her death in 1864, Thomas married Viola L. Davis in 1865 and became an Evangelical Lutheran minister.

In 1869, Thomas was appointed entomologist and botanist to the Geological Survey of the Territories, conducting research in the West until 1873. The Geological Survey of 1871, led by Ferdinand Vandeveer Hayden, explored northwestern Wyoming, leading to the creation of Yellowstone National Park in 1872. It was the first federally funded geological survey to explore and further document features in the region. During the expedition, Thomas, Charles Valentine Riley, and Alpheus Spring Packard studied the behavior of destructive western locusts, leading to creation of the United States Entomological Commission. They found the locusts' breeding ground, observed the effect of weather, and noted what determined their direction of spread.

Before 1871, the first board of trustees for Southern Illinois Normal College (later Southern Illinois University) commissioned Thomas to collect artifacts for a museum, located in the original Old Main building and opened to the public in 1874 when the college began holding classes. From 1874 to 1876, Thomas taught natural sciences at the teachers’ college.

In 1875, Thomas was appointed to the Illinois office of state entomologist. He had been publishing entomological papers since 1859, while he was practicing law. His research focused on insects that damage crops. While working as the state entomologist, Thomas also served with colleagues Riley and Packard for five years as a member of the United States Entomological Commission. In his later years, he turned to the study of ethnology and archaeology, studying the origins of mound builders in Illinois and Mayan hieroglyphics. Thomas died in 1910.

Learn more

Lentz, Eli Gilbert. 1955. Seventy five years in retrospect, from normal school to teachers college to university, Southern Illinois University, 1874-1949. Carbondale: University Editorial Board, Southern Illinois University.