A Histochemical Study of the Cytoplasmic Inclusions of the Epithelial Cells in the Epididymis of the Mouse

I . A histochemical study has been made of the cytoplasmic inclusions of the epithelial cells lining the storage section of the canal in the head of the epididymis of the mouse. 2. Spherical bodies, usually situated in the vicinity of the nucleus and here referred to as juxta-nuclear bodies, are shown to consist of cerebroside with some phospholipid. The juxta-nuclear bodies have been regarded by other authors as derived from the nucleolus, but there is no histochemical similarity. 3. A large supra-nuclear body exists, consisting of a matrix of protein and carbohydrate with enmeshed spheres. The latter do not colour with any dye or histochemical reagent used in this investigation. They are partially or completely surrounded by rims or crescents consisting wholly or mainly of lipid. 4. Droplets and much smaller granules are present in the region between the supranuclear body and the free border of the cell. The contents of the former show no histochemical evidence of the presence of organic matter, while the latter consist of protein and carbohydrate.