In this image of a woman on a flying carpet, the background is largely black-and-white, while the carpet and woman in the foreground show strong use of color. A cow is standing in the churchyard; the carpet has a horseshoe and a Hotei figure, or laughing Buddha. The drawing juxtaposes the ankh, Egyptian symbol of eternal life, with the Christian crosses on the church steeple and door.
Floyd R. Peterson 
Comments on: "Magic Carpet Ride" (2)
Sometimes I think Floyd took a break from the focus required to fill in those fine, precision shading/texture lines, and then never got back to it. So many of his drawings have unfilled areas. I suspect he may also have gotten a new idea in his head that took priority to finishing a previous work. I can relate to that! I think it’s interesting though as an example of his process… his use of line in various thickness, color, and density to illustrate those elements.
Or maybe those unfilled areas are there to add dimension, part of his artistic effect? I see your point, though, it can look artificial, especially on her legs in this one.