This is a newly-molted variable oakleaf caterpillar (Lochmaeus manteo), with old head capsule still attached. I initially thought the capsule was the head and that the thorax had eyespots, but John and Jane Balaban on Bugguide.net pointed out the obvious to me.
This species sprays formic acid, apparently.
FYI, Al Denelsbeck posted an almost identical image here, complete with close-up of the eyes.
This golden-backed snipe fly (Chrysopilus thoracicus) landed in one of my bird baths and drifted around for a few minutes on the surface tension. I’m not positive, but I think I’ve seen them do this in past years, too. I wonder whether they are looking for mosquito larvae, or perhaps adults. These flies have predaceous mouthparts, so they clearly hunt something. Sure wish somebody would PCR the gut contents of these things and let me know. Anyone ever seen them take something down?
Here’s another one, albeit one with a damaged eye: