After wiggling out of its old skin, the caterpillar then rubs off its FACE MASK. Even the face mask has become too small. The most amazing part is when the caterpillar turns around and EATS its own skin. Just like the eggshell that it ate for breakfast, the old skin is filled with vitamins to help our caterpillar grow big and strong. Kids love to collect the skins and face masks as the caterpillars grows. You can easily tape them onto a piece of paper for your science collection. Show all your friends!