Confidence: I'm as sure as I can be.
Notes: An old emperor moth cocoon found on open moorland. When opened up it appeared to contain many more small cocoons, empty ones. It seems this pupa was parasitised but I have no idea what species the parasite was? These small cocoons are similar in structure to small white parcels I found on a fox moth caterpillar at the same place last August, see 3rd pic.