Some cats that had me totally baffled for a couple of days until Reg Fry put me out of my misery. Sue and I spotted a large number of these cats feeding on Meadowsweet on the coast a week or so back. The large ones were around 1cm in length and the slightly different looking earlier instars were about .5cm in length. My first though was footman spp, no go as they all feed on lichens or dried plant material. I looked through every book I had, did searches for cats on Meadowsweet, even went through evey cat in Porter book and zilch. I posted the photos on Regs website and he came back with early instar Emperor Moth !!! I would never in a million years have got this despite rearing many through in the last instar and from pupa. I have never seen the early instars and to find them on Meadowsweet no more than 20 feet from the sea at low altitude was a complete shock.