I reached down into the water to pick up a beautifully patterned stone, only to discover that the 'covering' lifted up and elongated itself into what looked like a 'sucker fish,' with one end still attached to the stone. I put it into a bucket to photograph the lovely pattern on its back. It's the Smooth Turtle Leech (Placobdella parasitica), native to North America, which feeds on snapping turtles. It's nothing to be afraid of, it's just a worm that has 32 "brains," one on each segment - pretty neat.
"Remember, the attitude you display towards living things affects other people around you. Over-reacting to icky creatures imposes these attitudes on future generations. So, please, just relax, pick off the leech and flick it back into the water. Live and let live."
http://www.naturenorth.com/fall/leeches/Leeches_2.html