Like the ovary, in its earliest stages it consists of a central mass covered by a surface epithelium.

These cords run together toward the future hilum and form a network that ultimately becomes the rete testis.

It appears the function of the rete testis is to mix the sperm as they leave the seminiferous tubules.

Sperm leave the seminiferous tubules in the dilute secretions of Sertoli cells.

The rete testis does modify the luminal fluids with a limited amount of secretion and reabsorption, but their primary function is to mix and transport the sperm into the efferent ductules, where the major function is reabsorption of about 95% of the fluid, which increases the sperm concentration prior to entering the epididymis.