And notice that these seminar philosophy tubules eventually converge and form this highly convoluted structure known as the epididymis. Now, before we discuss what the function of the epididymus is, let's discuss what the function of the seminar fields tubule is and what the structure of the tubule looks like. So if we take a single seminiphers tubule and we take a cross section and we zoom in on that cross section, we get the following diagram. So we have the internal cavity, the lumen of the seminphilus tubule and this red portion is the wall of the seminaries seminipherous tubule. Now, if we further zoom in on a portion of the wall, we get the following diagram. And this is the diagram that describes the process of spermatogenesis, how sperm cells are actually formed.