Several years ago, a large erratic, some 20.0 m to the northwest of the turtle petroform was found to have an engraving along the top from south to north in the form of a pecked serpent. This pecking followed a linear fault in the rock, a kind of natural zig-zag depression. Such enhancements of natural features are alluded to in rock art terminology as iconic congruence. In this case, the zig-zag was enhanced by pecking and the anterior elements of the serpent image were engraved beyond the natural part to the north. A pecked widening of the image is noted at the head end, the contiguous pecking portraying a solid mass. This solid portrayal is common to Archaic rock art, and denotes a naturalistic/realistic dimension in the artistic conveyance – in other words, it shows real mass, not abstracted as outlining would do. The rock here is an igneous erratic, and more like the “hard rock” sites at Hensler and Observatory Hill in Marquette County. Such formations lend themselves to this type of conveyance, and nearly all the petroglyphs at Hensler are of this type. However, there are no known petroforms at the Hensler Site, nor are there any engraved monoliths.