Between 10 and 12 very convoluted efferent ductules, held together by loose connective tissue, emerge from the rete testis and fuse to form a single highly coiled duct which is the epididymis.
Notice that the external margin of tubules is regular due to the presence of smooth muscle fibres, but the luminal margin is very irregular because it is lined by alternating groups of tall and short cells. Some of the lining cells contain brown pigment granules.
