200 Years. 200 Stories. Story 180: ““Specimen” ”

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pinned specimen of a stag beetle
Lucanus capreolus (Linnaeus, 1763), the iconic Stag Beetle of Eastern State Penitentiary, collected in Cellblock 4, July 1, 2011.


Greg Cowper is more than a curatorial assistant in the Academy’s Department of Entomology. He’s also the mastermind behind the Specimen exhibit at Philadelphia’s Eastern State Penitentiary. Cowper’s installation was inspired by an article written by Dr. Henry Skinner, a medical doctor and late 19th-century entomology curator at the Academy. Skinner wrote the article after an encounter with a Penitentiary inmate’s insect collection, and Cowper’s work expands upon the prisoner’s assemblage. The prisoner, who was living in solitary confinement, gathered butterfly and moth specimens during his exercise periods in a narrow, high-walled exercise yard. Following a professional visit to the Penitentiary in 1889, Skinner published a brief report on this “Unique Collecting-Field” in the Entomological News and Proceedings of the Entomological Section, Academy of Natural Sciences, Philadelphia in 1890. After revealing that he was “mortified to find a lepidopterist” among the prison’s inmates, Skinner noted that the collection covered an impressive 17 butterfly and moth species, some of them quite rare, and one cicada species.

Cowper, emulating the prisoner’s methods, returned to Eastern State to build his installation. The specimens are all captured within the walls on penitentiary grounds and encompass more than 300 species of insects and other invertebrates. Enlisting the help of Academy Exhibits Preparator Mike Beers, Cowper houses the collection in a Cabinet of Curiosities crafted from old prison doors, hardware, and cigar boxes (the container of choice for amateur entomologists). The installation has become a natural history performance piece, constantly growing and evolving, as Cowper and penitentiary staff continue to retrieve more insects and other invertebrates. As Cowper delves deeper into the penitentiary’s cellblocks, the collection’s newest additions represent more than just invertebrates. His latest discoveries include a mummified cat and preserved bird whose appearance echoes the famous Berlin Archaeopteryx fossil—leading Cowper to christen the find Penitentopteryx.

Check out the Entomology Department to learn more about the Academy’s exciting insect-related projects, collection, and research.

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