A seashore souvenir is a popular item to bring back from a beach vacation. Two common items that are often found as seashore souvenirs are shells and conchs. Shells are the hard, protective outer layer of certain animals, such as mollusks and crustaceans. Conchs are large sea snails with a spiral SHELL. Both shells and conchs can be found in a variety of shapes, sizes, and colors, making them popular items to collect and display.