Plaster portrait bust on low columnar base. The subject has sideburns and shoulder-length hair, brushed back. He wears a waistcoat, a neckcloth and collar, and a heavy swath of fabric draped over his shoulders. Unsigned and undated. "Caspar Wistar" incised on verso of base.

Portrait of Erasmus Darwin, blue on white jasper dip. "Wedgwood/O" in capital letters on back, and "Dr. Darwin" in cursive on back. Tentatively attributed to Joseph Hackwood. After late 18th-century model by Joseph Wright.