Structural adaptation for reducing water-loss in three species of terrestrial snail

Laboratory measurements indicate that observed differences in the rate of water-loss from inactive Helix aspersa, Otala lactea and Sphincterochila boissieri are due to morphological adaptations such as a thicker shell, reduced aperture and thicker epiphragm. These modifications enable terrestrial snails to inhabit dryer environments by increasing the length of time the snail can remain inactive.