It's not poop....

Since about the third day of observing, I have noticed these small black dots on the bottom of the container. I just assumed that it was his poop only to discover that it is actually the sign that he molted--its his old layers. By the end of his caterpillar life, he will have molted about four or five times.As he grows he sheds one layer for a layer more suitable for his size. Currently there are three on the bottom of the container.