We've been finding these in the house, always on the kitchen floor. Started about 2 weeks ago. We see anywhere from 5-10 at a time and about 4 different days. So there several days we don't see them. I've checked all the pantries, cabinets, underneath appliances and trash cans for a source but can't find one. They move more like a caterpillar than a worm. They're about the length of a dime to penny. We don't see any flying insects either. What are they, where are they coming from and how do we prevent them?