Horse Leeches

These Leeches were found on the underside of a submerged log in a pool in Wigmore Field, Sandwell Valley, West Midlands, during an outing of the Sandwell Valley Naturalists' Club, 4 July 2001

I was told that they're Horse Leeches - note the observer , in the background!

Above and below are close- ups from the same original.