Fig. 6

Schematic drawing of the caudal organ of Crasiella diplura. The basal lamina, the circular musculature and the three ducts of the caudal organ are shown. The accessory duct is on a different focal plane, so it is hatched. The position of the two pores (arrows) of the main and of the accessory duct is clearly visible. acd accessory duct, ad anterior blind duct, bl basal lamina, cm circular muscles, md main duct, mi microvilli