Johann Conrad Peyer (26 December 1653 – 29 February 1712) was a Swiss anatomist who was a native of Schaffhausen.
He studied medicine in Paris under Guichard Joseph Duverney (1648–1730), in Montpellier under Raymond Vieussens (1635–1713) and received his medical degree in 1681 at Basel.
These anatomical structures are aggregated lymphatic nodules found in the lining of the small intestine.
He was also the author of an influential work on veterinary medicine titled Merycologia sive de Ruminantibus et Ruminatione Commentariae.
This Swiss biographical article related to medicine is a stub.