The scrotum, commonly called the "purse", is a bag in which the testes are suspended by the spermatic cord. It is composed of six layers, the chief of which are the skin and the dartos.
The skin is an extension of the common integument, but much thinner and more supple than that found in the more exposed parts of the body. It possesses, besides, a large number of sebaceous glands, whose unctuous secretion is constantly being thrown out to lubricate the surface. By this means the scrotum is enabled to move freely over the thighs without irritation.
Fig. 224. - Constituents of Spermatic Cord.
A, Vas Deferens or Spermatic Duct. B, Spermatic Vein. C, Spermatic Artery. D. Internal Abdominal Ring.
The dartos is a thin pinkish-yellow layer of involuntary muscle and elastic fibres, largely interspersed with connective tissue. It is situated beneath the skin, and forms a pouch for each testicle by interposing a partition (septum scroti) between one organ and the other.
Fig. 225. - View of the Male Genital and Urinary Apparatus.
A, Cowper's Glands. B, Prostate Gland, c, Dilated portion of Spermatic Duct. D, Vesicula Seminalis. E, F, Ureters. G, G, Spermatic Vessels and Duct passing through the internal abdominal ring on their way to the Testicle. H, Bladder. I, Layer of Peritoneum.
When the dartos contracts the testicle is raised in the purse; at the same time the skin is corrugated.