Larvae Worm

I am holding a round clear plastic cup with a medium size worm inside that has a yellowish color and It's not pleasant to look at. There is something else inside the cup that I am not sure what it is, I would like to know if they eat whatever is inside the cup. The worm has a dark head and there are lines all over its body. It does not have feet or tail but it has two brown eyes at the back of its body. There is also a circle around the brown eyes with things sticking out of it. When the worm moves, there is a long brownish line connected from the head to the back that looks like its spine.