The C. P. Gillette Museum of Arthropod Diversity has its roots in the college museum established in the early 1890s, which was organized to support the teaching of zoology and entomology. Named for Clarence Preston Gillette (1859-1941), creator of the museum and the first professor of entomology at Colorado Agricultural College (now Colorado State University), the museum changed considerably over the 20th century. First housed in Old Main and curated by E. L. Burnett, the museum’s location changed several times before it was disbanded in 1947, at which point the insect collection became the property of the Department of Entomology. In the early 1990s, department staff named the collection the C.P. Gillette Museum of Arthropod Diversity. The museum currently holds approximately three million insect specimens and a noted reference library. The museum’s records contain two accession ledgers, the papers of butterfly collector Ray E. Stanford, newspapers, papers, and books of museum fellow Richard Holland.

Accession catalogs for insects and other arthropods dated 1890 to 1972 are found in the Gillette (C.P.) Museum of Arthropod Diversity archival collection. Many of the specimens were collected by C. P. Gillette, and entries typically include location, date, collector, specific habitats information, hosts, and associated other species.

These digital collections include publications, conference proceedings, and the newsletter Papilio. New Series.