Here is a new, developing Monarch butterfly caterpillar, munching on a Swamp Milkweed flower bud. This little guy (gal?) is less than an inch (25mm)long and about 1/8 inch (4mm) in diameter at this point. I wonder if that might be its egg case on the stem at the right of the photo. Photographed in Churchville Park, west of Rochester, NY.