The structure of the duct and the tubules of the digestive diverticula in the snail, Semisulcospira libertina, was examined with histological sections. The tubules branched off dichotomously from several sites of the tubule system, after extended from the junction of both the tip and side wall of the duct. From the results of this experiment, the tubule pattern of the snail indicated the dichotomous branching type, and the duct was supposed to be undifferentiated to the main duct with the secondary duct.