A new theory of micturition and urinary continence based on histomorphological studies. 5. The musculus ejaculatorius: a newly described structure responsible for seminal emission and ejaculation.

Theories of seminal emission and ejaculation based on morphology especially of the dorsal longitudinal urethral muscle system are found very infrequently in the literature. Our own examinations carried out on serial sections of the whole distal urethral complex taken from 50 male and 15 female autopsy preparations prove that the dorsal longitudinal urethral muscle system represents an independent smooth muscle. In the female, the muscle system runs outside the sphincter system. In the male, it is the direct continuation of the musculature of the ejaculatory ducts and its expansion is generally restricted to the urethra below the colliculus seminalis. Within the urethra the urethral crest is protruded. Differences in the degree of the formation of the muscle in various age groups will be described. For this newly described muscle structure, we suggest the term musculus ejaculatorius as, due to purely anatomic reasons, an involvement in the process of ejaculation seems to be conclusive. A theory of seminal emission and ejaculation is given as a mass action of the musculature of the bladder neck.