The study of vitelline gland of Haploporus lateralis (Digenea: Trematoda).

The study of vitelline glands of digenean Haploporus lateralis, indicates that the glands consist of vitelocytes in various stages of maturation. The cytoplasmic process of nurse cells which surrounded the vitelline lobes, intrude between vitelocytes and surround them. Immature vitelline cells are undifferentiated, they possess small amount of cytoplasm and large nucleus. The synthesis of shell globules begin in the maturing vitelline cells. Increasing numbers of vitellocytes reach develop of mature vitelline cells. The cytoplasm of mature vitelline cells is filled with shell globules. Mature vitelline cells usually found in the center of vitelline lobe. They release into the vitelline duct and vitelline reservoir. The vitelline reservoir and duct are lined with a syncytial epithelium. Basement membrane is present between nurse cells and vitelline cells.