The dartos fascia is fatty-free fascial layer including smooth muscle fibers. It gives the scrotum its’ pigmentation and lies close to the surface of the scrotum to assist the cremaster muscle which is made of skeletal fibers to descend or wrinkle and draw closer to the body especially during times when the fight or flight nervous system is activated or during sex to prevent damage to the testicles.

Coverings of the Testis:

These layers are numbered according to their deep to superficial placement in the scrotal sac.

1. Tunica vaginalis (visceral layer) epi orchium

2. Tunica vaginalis (parietal layer) periorchium (from peritoneum)

3.  Internal spermatic fascia (from transversalis fascia)

4.  Cremaster muscle and fascia (from internal oblique muscle)

5.  External spermatic fascia (from external oblique muscle)

6.  Skin with the dartos fascia

The scrotum is divided internally by a continuation of the dartos fascia in the scrotal septum, into right and left compartments. The septum is demarcated externally by the scrotal raphe ( a seam like ridge between two similar parts of a body organ, as in the scrotum). The raphe is continuous with the dartos muscle which is superficial fascia that covers the dartos muscle and layers below that of the external spermatic fascia, cremasteric fascia, and internal spermatic fascia. Then beneath the internal spermatic fascia, there is the tunica vaginalis, a mesothelial layer which outlines a sac containing a testis, epididymis, and spermatic cord, usually together with a small amount of fluid. The layer of the tunica vaginalis lining the scrotal wall is defined as the parietal layer; the one extending over the testis and epididymis is called the visceral one.