The median vagina, spermatheca and ejaculatory duct are, on the other hand, formed by ectodermal inpushings.
Soon after quitting the uterus it is joined by a long duct leading from a glandular sac, the spermatheca (Rf).
In Helix hortensis the spermatheca is simple.
But in rare cases in Helix aspersa a second spermatheca is found at the end of this second duct.
Fertilization takes place as the egg is laid, the spermatozoa being ejected from the spermatheca of the female and making their way to the protoplasm of the egg through openings (rnicropyles) in its firm envelope.
In Heliodrilus the blind extremity of the spermatheca is enclosed in a coelomic sac which is in connexion with the sacs envolving the ovaries and oviducts.
Closed in a viscid secretion at the point where the albuminiparous gland opens into the duct intertwined with it; and on reaching the pcint where the spermathecal duct debouches they are impregnated by the spermatozoa which escape now from the spermatheca and meet the ova.