The appendix of the epididymis (or pedunculated hydatid) is a small stalked appendage (sometimes duplicated) on the head of the epididymis. It is usually regarded as a detached efferent duct.

This structure is derived from the Wolffian duct (mesonephric duct) as opposed to the appendix testis which is derived from the Müllerian duct (paramesonephric duct) remnant.

• Appendix testis

This article incorporates text in the public domain from page 1242 of the 20th edition of Gray's Anatomy (1918)

• MedEd at Loyola urology/torapx2.htm - Torsion of Appendix Epididymis
• Anatomy image:7754 at the SUNY Downstate Medical Center
• inguinalregion at The Anatomy Lesson by Wesley Norman (Georgetown University) (testes)