Why do snails melt when they come in contact with salt?

All of the answers that have been provided that mention or explain how the diffusion of water takes place because of the high concentration of salt on the skin of the slug are correct to a degree, but leave out a couple things. read more

Technically, they don't melt, they shrivel. Snails and slugs have an outer mucous membrane with water-based slime on the outside, The salt dissolves in this slime, forming a highly concentrated solution of salt. read more

Also, the snails I’m picking tend to be out when the plants they’re sliding on are wet with dew. Between the mucus and the dew, there’s enough water clinging to the outside of the snail to dissolve some salt and put the membrane in contact with a very salty solution. read more

When salt comes into contact with the skin of a slug or snail, osmosis drags water out through the cells lining the skin due to the sudden high concentration of a pure salt crystal on the surface of its skin. Certain species can deal with small crystals of salt by excreting large amounts of mucus in the area, reducing contact and water loss. read more