A reader wrote to us a while ago about a worm that can “stand up on end and bite or bore into” skin. The worm is about a quarter of an inch long and moves like an inchworm, which is in fact a type of caterpillar, but then once it is ready to bite, “it raises up on end and tries to worm its way into the skin.” The reader has a young daughter who loves to play outside, so he is keen to find out what the biting worms may be. He hasn’t been able to take a picture of the worms that bite, nor has he been able to find out any information about them. What might these biting worms be?