Typical Snail Reproduction

Most terrestrial snails are hermaphroditic.  This means that each individual snail possesses both male and female reproductive organs.  This type of reproduction increases the chance of new colonization of the species, because more offspring can be produced.  The age at which snails reach sexual maturity varies among species, and it may take up to three years before snails are old enough to reproduce.  Mature snails begin mating in early summer.  Both individuals involved lay fertilized eggs in nests dug out of moist soil.  The snails lay several dozen eggs, then cover them with soil where they stay until they are ready to hatch.

 

Torsion

Torsion is an anatomical event that is part of the process of development for snails and slugs of all kinds.  This process occurs very early in a gastropod's life cycle in the larval stage of development.  Torsion is the term to describe the 180 degree rotation of the visceral mass, mantle, and shell, with respect to the head and foot of the gastropod.  Torsion results in bringing the mantle cavity and anus to an anterior position.