[Segmentation of the epididymal duct in mouse: an ultrastructural study].

The cytology of epithelial cells of the mouse epididymis was studied under light and electron microscopy. Four principal areas--the initial segment, the head, the body and the tail--were distinguished according to the morphological features of the main cells. Transitional areas separating these segments have been described also; one of the segments, intermediate between the head and the body, was longer. Five other cell types and their sites were noted: "apical" cells, corresponding to the "narrow" cells of Sun and Flickinger (1980), were located in the initial to the intermediate segment; clear cells were scattered in the epithelium from the intermediate segment to the tail; basal cells were sporadically distributed along the entire duct. Halo and dark cells were observed also.