Uterus Masculinus. a part of the urogenital system in the males of certain vertebrates, for example, elasmobranchs and mammals. In a number of animals, including primates, rodents, and lagomorphs, the uterus masculinus becomes the prostatic utricle, which fills the prostate gland with secretions during sexual activity.

Understanding Uterus-Masculinus in Mammals
The uterus-masculinus, also known as the male uterus, is an anatomical structure in certain male mammals. Its development is tied to specific embryological origins.
Embryological Origins
- The uterus-masculinus is derived from the Müllerian duct.
- During embryonic development, both male and female embryos initially possess Müllerian ducts, which can develop into female reproductive structures.
Role of the Müllerian Duct
- In males, the presence of testosterone leads to the regression of the Müllerian ducts. However, in some mammals, remnants of these ducts can persist and form the uterus-masculinus.
- This structure is not functional in the same way as the female uterus, but its presence indicates the historical embryological pathways shared by male and female mammals.
Comparison with Other Ducts
- Inguinal Canal: This canal is associated with the descent of the testes in males and is not involved in the formation of the uterus-masculinus.
- Wolffian Duct: Also known as the mesonephric duct, it develops into male reproductive structures (e.g., epididymis, vas deferens) but does not contribute to the uterus-masculinus.
- Ejaculatory Duct: This is formed from the fusion of the Wolffian duct and the seminal vesicle, playing a role in male reproduction but unrelated to the uterus-masculinus.
Conclusion
The correct answer to the question about the origin of the uterus-masculinus in mammals is indeed option C) Müllerian duct. Understanding this structure highlights the fascinating aspects of mammalian embryology and the complexities of reproductive anatomy.