The world's oceans are home to many species of mollusks, impressive with a variety of colors, sizes and shapes of shells. The shell of mollusks is a formation secreted by the mantle of their body. It is made of three layers: the outermost is horny, the middle is limestone, and the inner is mother-of-pearl. In snails the shell is single, and in mussels it is composed of two halves joined at the tip. The latest exposition of the Natural History Museum in Burgas is dedicated to the inhabitants of the World Ocean. The specimens presented in the window are not found in our Black Sea and can be seen in Burgas only in the museum hall. If you want to see some of the largest representatives or one of the most tender and beautiful, come and visit the museum at 30 K. Fotinov Street, every day from 10:00 to 19:00.