Photographed on an alder shrub in mid-summer in the Mer Bleue area. These are spectacular caterpillars which turn into even more spectacular moths, about the size of a hand. They belong to the giant silkworm family and this caterpillar, when it grows quite a bit bigger than this, will eventually weave a large cocoon of brownish silk, papery in appearance and spend the winter in it until spring rolls around http://www.pbase.com/laroseforest/image/148372812).