Henry Gray (18211865). Anatomy of the Human Body. 1918.
3c. 7. The Bulbourethral Glands
(Glandulæ Bulbourethrales; Cowpers Glands)
The bulbourethral glands are two small, rounded, and somewhat lobulated bodies, of a yellow color, about the size of peas, placed behind and lateral to the membranous portion of the urethra, between the two layers of the fascia of the urogenital diaphragm. They lie close above the bulb, and are enclosed by the transverse fibers of the Sphincter urethræ membranaceæ. Their existence is said to be constant: they gradually diminish in size as age advances.
The excretory duct of each gland, nearly 2.5 cm. long, passes obliquely forward beneath the mucous membrane, and opens by a minute orifice on the floor of the cavernous portion of the urethra about 2.5 cm. in front of the urogenital diaphragm.
Structure.Each gland is made up of several lobules, held together by a fibrous investment. Each lobule consists of a number of acini, lined by columnar epithelial cells, opening into one duct, which joins with the ducts of other lobules outside the gland to form the single excretory duct.