The ductuli efferentes of the epididymal region of birds.

Ultrastructural studies were undertaken on the efferent ductules of the testis of the domestic fowl (Gallus domesticus), Japanese quail (Coturnix coturnix japonica) and guinea-fowl (Numida meleagris). Four cell types were identified and described: ciliated cells which were found in the epithelium of both the proximal and distal segments of the efferent ductules, non-ciliated Type I cell which, together with the ciliated cell, formed the epithelium of the proximal efferent ductule and the non-ciliated Type II cell which, together with the ciliated cell, formed the epithelium of the distal efferent ductule. Intraepithelial lymphocytes were the fourth cell type found in the epithelium of both segments of the efferent ductule of the fowl only.