The present study deals with the anatomy of Semisulcospira bensoni. Though the shells of this feesh-water snail are sexually indiscriminate, the female snail is easily distinguished from the male by the presence of the brood pouch, and by the difference in shape between the testis and ovary in breeding season. The excretory opening of the kidney is situated at the apicalmost part of the mantle cavity and the excretion is carried by the exhalant ciliary current observed on the outside of the prostate gland in male or of the accessory gland and brood pouch in female. The male copulatory organ was not defined. The arteries are feebly developed, while the sinus are well developed, being dark green in colour due to the presence of haemocyanin. The central nervous system is composed of 11 ganglia, and the connectives between them are long, above all, that between the right pleural and supra-oesophageal ganglia being longest. The visceral ganglion is composed of 2 lobes. The stomach consists of 2 parts of lumen, the anterior of which has many complicated muscular folds on the inner surface and the posterior is dorsoventrally divided by typhlosoles into the crystalline style sac and intestine.

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