Abstract
The reproductive system of an estuarine pulmonate snail Ellobium chinense was studied. The ovotestis of this species is embedded deeply among lobules of the digestive gland forming a cluster of rounded acini which is yellowish-orange in colour. Though the acini contain both eggs and sperms together, during some portion of the year, there are two pronounced phases of sperm production and egg production, taking place successively. At the base of the albumen gland, the hermaphrodite duct bifurcated into male and female ducts, and two ducts are closely associated as a parallel pair (Text-fig. 1.). Separating from the hermaphroditic duct at the carrefour, the male duct proceeds to the penis located behind the right tentacle. Along its course the most part of the duct, which is attached to the glandual portion of the female, is provided with prostatic material. On the other hand, the female duct separating from the hermaphroditic duct continues to a large thin-walled cavity, fertilization chamber, enclosed by the mucus gland, and also receiving the secretion of the albumen gland. The duct of the bursa copulatrix is long and open into the vagina and the male duct. The whole of the secreting portion of the female genital tract is thus separated from the path of the sperms, and the genital system in Ellobium chinense is completely divided into male and female duct. The vas deferens with no gland begins at the place where the duct of bursa copuratrix is open to the genital duct and continues to the penis, as a narrow tube enclosed in the ridge of the genital groove.
