... among the poor and uneducated, where filth and untidiness reign, the "itch" is a very prominent disease. It is caused by the itch mite, a parasite which burrows underneath the skin leaving behind its eggs in little irregularly shaped, bluish tinted ridges. Such a profound itching is set up by this burrowing and depositing of eggs that the child ... — The Mother and Her Child • William S. Sadler