A reader wrote to us the other day about some small white larvae she found all over a towel on the floor of her home. Apart from being quite small – they are about a half centimeter in length at most – they also have a black interior, almost as if a black larva lived within the white larva. The larvae are therefore almost clear – they are see-through in the way that a light-colored mound of Jell-O might be. The reader is wondering what these creatures are and is concerned about their presence, primarily because she has small children in the house. So, what are the small, white larvae (or clear larvae) with the black insides that our reader recently found?