The seminal glands (Seminal vesicles) are two lobulated membranous pouches, placed between the fundus of the bladder and the rectum, serving as reservoirs for the semen, and secreting a fluid to be added to the secretion of the testes. Each sac is somewhat pyramidal in form, the broad end being directed backward, upward and lateralward. It is usually about 7.5 cm. long, but varies in size, not only in different individuals, but also in the same individual on the two sides.
The anterior surface is in contact with the fundus of the bladder, extending from near the termination of the ureter to the base of the prostate.
The posterior surface rests upon the rectum, from which it is separated by the rectovesical fascia.
The upper extremities of the two vesicles diverge from each other, and are in relation with the ductus deferentes and the terminations of the ureters, and are partly covered by peritoneum.
The lower extremities are pointed, and converge toward the base of the prostate, where each joins with the corresponding ductus deferens to form the ejaculatory duct. Along the medial margin of each vesicle runs the ampulla of the ductus deferens.
Each vesicle consists of a single tube, coiled upon itself, and giving off several irregular cecal diverticula; the separate coils, as well as the diverticula, are connected together by fibrous tissue. When uncoiled, the tube is about the diameter of a quill, and varies in length from 10 to 15 cm.; it ends posteriorly in a cul-de-sac; its anterior extremity becomes constricted into a narrow straight duct, which joins with the corresponding ductus deferens to form the ejaculatory duct.
Structure.—The vesiculæ seminales are composed of three coats:
Vessels and Nerves :