An ichneumon wasp laid an egg in this caterpillar which ultimately died providing sustenance to the internal parasitoid. The caterpillar's corpse is here seen attached, with the cocoon of the wasp, to the leaf where the wasp larva emerged to pupate. It will spend the winter attached to the withered leaf and an adult will emerge next summer. The cocoon is 5.5mm long and 3mm in diameter. The brown spots are believed to be fecal material incorporated into the cocoon. I am grateful to Anthony Thomas for identifying the cocoon and explaining the process to me. Tony thinks the wasp is probably in the subfamily Campopleginae of the Ichneumonidae.