Purple is a winter favorite at Eagle Lake, CA.. There is a color progression of the large leeches at Eagle Lake. In the spring they are a light brown. During the summer the brown gets much darker, “Night Crawler” brown. Finally, as the water gets cold, they take on a purple hue.

I have dyed a lot of materials to brown. After the hot dye bath, the color is fixed with a cold-water rinse. During the rinse process the dark brown gets washed out and the residual dye is purple. Purple is a constituent color of brown. My conclusion is that the progression of light brown, dark brown then purple is that all three of these are shades of the same color.