Fertilisation pocket.

The simple columnar ciliated epithelium of the hermaphrodite duct undergoes an abrupt transition to a thick, pseudostratified, ciliated epithelium with a minutely lobulated surface upon reaching the fertilisation pocket. At the level of entry of the hermaphrodite duct and albumen canal, the pocket is U-shaped in cross section, but expands dorsally to form an irregular chamber with thick walls composed of irregularly-shaped cells with basal nuclei and minutely granulate cytoplasm. A thick connective tissue sheath supports the fertilisation pocket, and strands of connective tissue pass through its walls. Close to the origin of the sperm duct the pocket is lined by ciliated cuboidal epithelium containing a few scattered large goblet cells.