Black Racer shedding

Today's trek took me through two states, one swamp, several upland forests, and, finally, to the rocky outcrops of Ell Pond in Hopkinton, Rhode Island. Ell Pond, now a Nature Conservancy sanctuary, is one of my favorite places on Earth, and I was there to show it off to a new friend who had asked me to help him assess moss and lichen habitats as potential field trip locales for a program he was putting together. In a cleft in one of the boulders at the height of land, I spotted this serpent emerging from its hiding place. Based on the white throat and the lack of keels on the scales, I suspect this is a Black Racer, the other black snake in our area. I'm being a little circumspect because there seemed to be more white on the belly than is typical in this species, and the fact that it's about to shed its skin makes it hard to see both keels and color. The fact that we could see it at all is probably not diagnostic. Black Rat Snakes, the more common dark serpent, tend to hold their ground when observed; Racers are so fast to retreat that you often never get so much as a dark glimpse. But this one, afflicted with temporary, pre-shedding cataracts, could barely see anything. However, it could still smell us and feel our presence through vibrations, so it slid back to safety. The retreat was uncharacteristically slow; I got some good closeup shots.