C. hortensis is a simultaneous hermaphrodite. A mating couple approach each other and try to manoeuvre into position to shoot a sharp dart of crystalline calcium carbonate into the body wall of the other by forceful eversion of its containing dart sac (1). The dart is coated with mucus from a pair of 4-branched (sometimes 5-branched) mucus glands (2) connected close to the opening of the dart sac. Lodi & Koene (2016) think the mucus, if injected, impedes the recipient’s reaction of destroying some of the sperm inserted so as to leave some ova to be fertilized by other individuals.
34 Cepaea hortensis. Dissection with mantle and body wall removed; organs as uncovered, undisturbed. Pennine foothills, V.C. Derbyshire, England. September 2018.
