The start of snail reproduction begins when one specimen mounts the shell of its partner and positions itself so that the genital pore side of both snails line up with each other (Webb, 1943).  The snail on top crawls forward toward the aperture (opening) of the bottom snail (Webb, 1943).  After the top snail reaches the rim, it positions its head and neck downward, while the lower snail reaches its head and neck upward (Webb, 1943).  The upper animal then crawls forward and when it reaches the aperture rim, its head and neck are thrust downward while the lower animal arches its head upward, so the snail heads come into contact (Webb, 1943).  While this is going on the sex organs are extruded (Webb, 1943).  Because the snails' heads are so closely pressed together and partially crossed during the gnawing procedure, it is impossible to see the genital pore and the sex organs are only seen when they are fully enlarged (Webb, 1943).  After the gnawing procedure has ended, the snails insert their respective penises into its partner's vagina (Webb, 1943).  At about the time each snail's penis is inserted into the other's vagina the animals cease to gnaw at each other (Webb, 1943).  These snails will go on to deposit the eggs created during fertilization in a secluded place that is not to wet that mold can grow and not to dry that the eggs dry out. Snail reproduction can de deemed internal fertilization between two hermaphroditic organisms because sperm is directly transferred and snails possess both male and female body parts.

Penis. -A snail's fully exerted penis appears  club-shaped and is lined with papillae (Webb, 1943).  The papillae decrease in size as you move up the penis, with the base of the penis being stalk-like (Webb, 1943).  A fully everted penis is about 11mm long, with expansion going upward from the base (Webb, 1943).    The inside  of the sac is filled by an irregular opaque mass and connects to the the penis below the surface, with the opening of the penis being on the distal end, and the opaque mass most likely being sperm (Webb, 1943). 

Snail Penis

Female-organs. -  Sexually active and resting snails have the same sexual organs (Webb, 1943).  During intercourse the penis occupies the vaginal cavity and the vagina is connected to hermaphroditic duct or uterus by a sigmoid flexure, a flexure is just a bend or curve in an organ (Webb, 1943).   By viewing the female organ structures it can be assumed that the oviduct below the sigmoid curve is actually part of the vagina, while the flexure, or curve, and remaining parts can be deemed part of the free oviduct (Webb, 1943).  It can then be assumed that all the surrounding parts of the vagina are part of the female reproductive parts of a snail.