Having found one of these caterpillars a few days ago, I was hoping to find another and get a better shot. The first one I found was in the east end of Ottawa, this was in the west end, and was also on Queen Anne's Lace. It has just started decorating its body with fresh bits of the flowers. You can see one white bit of plant matter on it, and lots of dried (old) bits of plant matter. This caterpillar turns into a pretty bright green moth.