As in other pulmonate gastropods, the ovotestis of adult Helix aspersa is
composed of a large number of tubules (acini) connected with the hermaphroditic
duct. These tubules contain male and female cells. The cells of the female germ
line are localized inside the « germinal epithelium » lining the acini. The youngest
female cells are located in the proximal part of each acinus, whereas the larger ones complete differentiation at the bottom (fig. 11. The development of these
cells has been subdivided into six stages (summarized in table 1) according to
size, cytological, cytochemical and ultrastructural characters and to their relationship
with the neighbouring cells.