part of part of develops from develops from epididymis mesonephric duct mesoderm-derived structure vestigial structure appendix epididymis http://upload.wikimedia.org/wikipedia/commons/4/4d/Gray1148.png Wikipedia:Appendix_of_epididymidis MA:0003245 appendix epididymis FMA:18268 appendix of epididymis UBERON:0006641 appendix epididymidis On the head of the epididymis is a small stalked appendage (sometimes duplicated). It is named the appendix of the epididymis (or pedunculated hydatid), and is usually regarded as a detached efferent duct. This structure is derived from the Wolffian duct as opposed to the appendix testis which is derived from the mullerian duct remnant. EMAPA:19086 appendix of the epididymis epididymal appendix epididymis appendix