We had been looking forward to a garden full of butterflies after finding some yellow eggs on the underside of  the leaves of my Chinese  mustard. They hatched out into caterpillars of the Large White, but we didn't mind as the Chinese Mustard had bolted and we have enjoyed watching them grow and shed their skins. Not many seemed to get eaten by birds who apparently find them bitter and they didn't seem affected by being out in scorching sunlight all day. Numbers dropped as individuals went off to pupate on the walls of the house and in the house! Several stayed motionless on the plant and then we saw one surrounded by little yellow cocoons and another with  little green larvae coming out of its sides. There are now about a dozen parasitised in such a fashion. The caterpillars are not dead yet even after three or four days but are incapable of crawling away from the cocoons which they are on top of. If I touch one the front end rears up very suddenly, which would surprise any predator, so the parasites are benefiting from this and the caterpillars bitter taste. In the picture of the larvae hatching out there is a ruby coloured insect on the head of the caterpillar and I wondered if this was coming to lay its eggs in the larvae!