Tubules of digestive diverticula in 4 species of Neritopsidae and in 12 species of Discopoda were observed by means of the tissue preparations by Azan staining. In 4 species of Neritopsidae, the tubule grew from the places on the ducts which extended from the stomach, ramified by the Monopodial branching type and developed out at the digestive diverticula. In 12 species of Discopoda, the long duct with large diameter which grew from the stomach extended in the inside of the spiral digestive diverticula, and the ducts with small diameter extended outside the spiral digestive diverticula from the places on the long duct. The tubules outgrew from the ducts with both the large and the small diameters, ramified by the Dichotomous branching type and developed out at the digestive diverticula.