Where the vesiculae join the ampullae of the vasa deferentia the ejaculatory ducts are formed; these are narrow and thin-walled, and run, side by side, through the prostate to open into the floor of the prostatic urethra.
The vesiculae seminales are muscular sacs with a mucous lining which is thrown into a series of delicate net-like folds.
Ischio-rectal fossa Tuberosity of ischium Gluteus maximus The vesiculae seminales are sac-like diverticula, one on each side, from the lower part of the ampullae of the vasa deferentia.
The accessory generative glands are the two vesiculae seminales, with the median third vesicle, or uterus masculinus, lying between them, the single bilobed prostate, and a pair of globular Cowper's glands.
Each opens in a vas deferens which bears three diverticula or vesiculae seminales, and three pairs of cement glands also are found which pour their secretions through a duct into the vasa deferentia.
Prostate glands and, except in the Duplicidentata, vesiculae seminales are present in all.
Usually each tube is provided with caecal appendages on its proximal portion, and these serve as vesiculae seminales, while the distal portion is enlarged and glandular and secretes the egg-shell.