Figure 1.

Basic organizational patterns of the rete testis and efferent ductules in small and large mammals. (A) In smaller mammals, such as rats and mice, the rete testis forms flattened chambers adjacent to the tunica albuginea of the testis, where sperm and tubular fluids are released into 3-7 efferent ductules that merge to form a single, highly convoluted common duct that enters the initial segment epididymis. (B) In larger mammals, including dogs and man, the rete testis forms flattened chambers surrounded by dense connective tissue within the mediastinum of the testis, which drains toward the efferent ductules that occupy a major portion of the caput epididymis. Most of the efferent ductules open individually into the caput epididymis.