found this group of Milkweed Tussock caterpillars in the
process of skeletonizing a milkweed leaf. When I approached
to shoot a few photos, the entire group began to thrash wildly
in defense -- mainly raising their longer pencils and waving
heads around in a somewhat similar synchronized twitching such
as that typical of sawfly larvae when disturbed. Location of
this sighting was alongside Black Ance Road.